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MATERIAL l'OR l'APKR-MAKI.W. 



An endless cable carries the blocks of wood along a chute from the sawmill. Through 
openings in the side of the chute the blocks are dropped at any desired point, subsequently to 
be transferred to the grinding-room. 



Science in the 
Industrial World 



BY 

HENRY SMITH WILLIAMS, M.D., LL.D 



ASSISTED BY 

EDWARD H. WILLIAMS, M.D, 



NEW YORK and LONDON 

THE GOODHUE COMPANY 

Publishers - mdccccxi 



*\ 



6 



m>a 




Copyright, igio, by The Goodhue Co. 
Copyright, iqn, by The Gciodhik Co. 

A II rights reserved 



\l 



CLA30014! 

wo. I 



CONTENTS 



CHAPTER I 

THE DEVELOPMENT OF THE TELEGRAPH 

Fundamental discoveries, p. 4 — Plan suggested early in the eight- 
eenth century, p. 5 — Some early experiments, p. 8 — The telegraph 
of Alexandre, p. 9 — Galvanism gives a new stimulus to inventors, 
p. 11 — Sommering's telegraph, p. 12 — Electro-magnetism gives new- 
clues, p. 14 — Experiments on magnets, p. 16 — The first practical 
telegraph system, p. 16 — Antecedents and early experiments of 
Morse, p. 18 — Morse's first public exhibition of his telegraph, p. 20 
— A regrettable controversy, p. 2 1 — Principle of the Morse telegraph, 
p. 23 — Multiple messages, p. 25 — Gray's "Harmonic Telegraph," p. 
26 — Telegraph recorders, p. 28. 

CHAPTER II 

THE SUBMARINE CABLE 

England linked with the Continent, p. 31 — Cyrus Field projects 
the Atlantic Cable, p. ^^ — Doubts of the scientists, p. 34 — High 
hopes — and failure, p. 35 — A second fiasco, p. 37 — Success at last, 
p. 39 — Improved methods and new cables, p. 40 — The cable of '65, 
p. 41 — The Great Eastern pressed into service, p. 43 — Instrumental 
aids, p. 45- 

CHAPTER III 

WIRELESS TELEGRAPHY 

Water and earth as conductors, p. 48 — Discoveries of Professor 
Trowbridge of Harvard, p. 49 — The wireless telegraph of Smith and 
Granville, p. 51 — Experiments with "Hertzian waves," p. 52 — 
Dr. Branly's coherer, p. 53 — The work of Marconi, p. 54 — Methods 
and results, p. 56 — Marconi's early attempts, p. 58 — Practical dem- 
onstration of the usefulness of wireless on ships, p. 59 — Trans- 
Atlantic messages, p. 60 — Tuning the messages, p. 61 — The prac- 
tical status of wireless telegraphy, p. 63 — Wireless in the Russo- 
Japanese war, p. 65. 

[Hi] 



CONTENTS 



CHAPTER IV 

THE DEVELOPMENT OF THE TELEPHONE 

Early experiments of Hauksbee, p. 67 — An early conception of the 
telephone, p. 68 — Wheatstone's ".magic lyre telephone," p. 69 — 
Bourseul suggests an electrical telephone, p. 71 — An interesting 
coincidence, p. 73 — Dr. Graham Bell describes his invention, p. 
74 — His studies of Helmholtz's experiments, p. 75 — Different kinds 
of currents, p. 77 — A human ear used in the experiments, p. 79 — 
Bell versus Gray, p. 81 — Practical improvements, p. 83 — Telephone 
equipment, p. 85 — Telephone exchanges, p. 86 — Automatic tele- 
phone systems, p. 87 — The wireless telephone, p. 88 — Instruments 
of Dr. DeForest, p. 90 — Working of the wireless telephone ex- 



plained, p. 91. 



CHAPTER V 

THE EDISON PHONOGRAPH 

Edison's early patents, p. 93 — The phonograph of 1877, p. 94 — 
Clockwork and electricity for rotating the cylinder, p. 95 — How the 
sounds are recorded on the wax cylinder, p. 96. 

CHAPTER VI 

PRIMITIVE BOOKS 

Assyrian and Egyptian books, p. 99 — Terra-cotta books of the 
Babylonians and Assyrians, p. 102 — The palm-leaf books of the 
Hindus, p. 106 — Folded books, p. 107 — The text of ancient books, 
p. 112. 

CHAPTER VII 

THE PRINTING AND MAKING OF MODERN BOOKS 

The invention of printing in the West, p. 120 — Gutenberg's press, 
p. 121 — The cylinder press invented, p. 123 — Napier's press, p. 124 
— The Hoe cylinder press invented, p. 125 — The advent of the 
"type-revolving machine," p. 126 — The press invented by Richard 
M. Hoe, p. 127 — Method of casting stereotype plates invented, p. 
128 — The introduction of "web" presses, p. 129 — A modern news- 
paper press, p. 131 — Speed of the perfecting press, p. 133 — A per- 
fected magazine press, p. 135 — Color-printing on rotary presses, 
p. 138 — Other aids to the printer, p. 139 — Type-setting machines, 
p. 141 — The Mergenthaler linotype, p. 142 — The Lanston mono- 



[iv] 



CONTENTS 

type machine, p. 145 — The graphotype, p. 148 — Other type-setting 
machines, p. 150 — Mechanical type-setting and distributing, p. 151 
— Bookbinding, p. 153 — Materials used in the early days of book- 
binding, p. 154 — Hand binding, p. 156 — Mechanical bookbinding, 
P- i57. 

CHAPTER VIII 

THE MANUFACTURE OF PAPER 

The Moors as paper-makers, p. 160 — Early paper-making in Europe, 
p. 161 — Making paper by hand, p. 162 — The "watermark," p. 
163 — Modern rag-paper, p. 164 — Manipulation of the rags in the 
factory, p. 165 — Accidental discovery of the use of bluing in paper- 
making, p. 167 — The pulp, p. 168 — How the pulp is transformed 
into paper, p. 169 — Paper from wood pulp, p. 171 — Pulp grinding 
discovered in Germany, p. 172 — How the paper for "greenbacks" is 
made, p. 175 — Watermarks and special papers, p. 176 — Calendered 
papers and "coated" papers, p. 178 — Special uses of paper, p. 179 
— Paper car wheels, p. 180. 

CHAPTER IX 

THE REPRODUCTION OF ILLUSTRATIONS 

Early wood-engraving, p. 184 — The oldest wood cuts, p. 186 — 
How light and dark effects are produced, p. 187 — The pictures of 
Albrecht Diirer, p. 188 — Technic of wood -engraving, p. 189 — Time 
consumed in making a wood-engraving, p. 190 — Copper- and steel- 
plate engravings, p. 192 — The invention of the Florentine goldsmith, 
p. 193 — Etching, p. 195 — Mezzotint, p. 196 — The invention of 
lithography, p. 197 — Materials used in lithography, p. 199 — The 
introduction of process work, p. 202 — The half-tone, p. 205 — How 
the "screens" are prepared, p. 208 — Three-color process of repro- 
duction, p. 211 — Color niters, p. 213 — Intaglio processes, p. 217. 

CHAPTER X 

PHOTOGRAPHY IN ITS SCIENTIFIC ASPECTS 

The fact that light causes chemicals quickly to change color dis- 
covered by Scheele in 1780, p. 220 — Tentative efforts, p. 222 — 
The Daguerreotype, p. 224 — First portraits ever taken, p. 226 — 
Talbot's "calotype" process, p. 227 — Glass negatives, p. 229 — 
Collodion-emulsion process, p. 231 — The flexible film invented, p. 
233 — Photographing in natural colors, p. 235 — The explanation of 



[v] 



CONTENTS 

the "standing" wave, p. 236 — Lippmann's direct method of color 
photography, p. 237 — Improvements in lenses, shutters, and 
cameras, p. 238 — Method suggested by Ducos du Hauron, p. 241 
— The Joly plate, p. 242 — The Lumiere process, p. 243 — The 
method of Jan Szczepanik, p. 245 — Improved method of M. Andre 
Cheron, p. 246 — The future of color photography, p. 247 — Chrono- 
photography — moving pictures, p. 248 — Edison's kinetoscope, 
p. 251— -How moving pictures are made, p. 252 — The uses of pho- 
tography, p. 255. 

CHAPTER XI 

PAINTS, DYES, AND VARNISHES 

The pigments of antiquity, p. 265 — Black pigments, p. 267 — White 
pigments, p. 274 — Some "chrome" pigments, p. 281 — Other yellow 
mineral pigments, p. 285 — Some brilliant but poisonous pigments, 
p. 288 — Green mineral pigments, p. 302 — Pigments from vegetable 
and mineral sources, p. 303 — The coal-tar colors, p. 311 — Dyes, p. 
314 — Varnishes, p. 316. 

Appendix p. 2> 2 2> 



[vi] 



ILLUSTRATIONS 

MATERIAL FOR MAKING PAPER Frontispiece ^ 

SAMUEL F. B. MORSE Facing p. l8 V 

MECHANISMS INVOLVED IN WIRELESS TELEGRAPHY . . " 60 l^ 

DR. GRAHAM BELL IN NEW YORK COMMUNICATING FOR 

THE FIRST TIME WITH CHICAGO BY TELEPHONE . " 74^ 

MESSAGES BY WIRELESS TELEGRAPH AND WIRELESS 

TELEPHONE " 88 v ' 

AN EARLY TYPE OF PRINTING-PRESS " 122 ^ 

A VIEW IN THE PRESS-ROOM OF HARPER & BROS., NEW 

YORK CITY " I38 V ' 

MANUFACTURE OF PAPER " 170 '' 



PULP-GRINDING MACHINERY 1 74 

THE FLYING MACHINE OF MR. GLEN H. CURTIS A RE- 
MARKABLE EXAMPLE OF INSTANTANEOUS PHOTOG- 
RAPHY " 232 



• 



[vii] 



SCIENCE IN THE INDUSTRIAL WORLD 



IN the present volume we are concerned with the 
application of relatively few and comparatively 
simple principles of science to a great variety of 
industries. So far as these industries can be grouped 
it may be said that they have to do very largely with 
the transmission of ideas. 

We shall hear the story of the development of the 
telegraph, cable, and telephone, those weird, even if 
familiar, mechanisms through which human ideas 
are flashed instantaneously from one part of the globe 
to another. 

We shall examine that even weirder mechanism, the 
phonograph, which embalms, as it were, and reproduces 
the very intonations of the human voice. 

We shall outline the story of bookmaking, from the 
papyrus scroll of the Egyptian and the clay tablets 
of the Babylonians to the astoundingly multiplied 
output of the printing-press. 

We shall learn also the story of paper-making, of 
the reproduction of illustrations, and of the making 
of those strangely realistic sun pictures called photo- 
graphs, which even now seem mysterious and wonder- 
ful to the thoughtful mind despite their familiarity. 
The presentation of these and sundry other aspects of 
modern civilization, as influenced so enormously by 

VOL. VIII. — I [ I ] 



SCIENCE IN THE INDUSTRIAL WORLD 

the application of scientific ideas, makes up a volume 
whose content should appeal to the most practical of 
readers. 

For the most part the industries here represented 
are essentially and characteristically modern. Book- 
making is indeed an ancient art, and paints and dyes 
of a crude type are manufactured even by barbarians. 
But telegraph, cable, telephone, and phonograph are 
affairs of the nineteenth century; photography is of 
contemporary origin; and even the older industries 
have undergone metamorphoses within the past gen- 
eration that are all but revolutionary. 

Attention has been called more than once to the 
extraordinary changes in the aspects of every-day 
civilization that industrial developments in other fields 
have wrought within the past half century; but no- 
where else, perhaps, have there been changes so far- 
reaching in their influence upon international relations 
on the one hand and upon the details of the most mod- 
est domestic economy on the other, as those which 
have been effected through the application of electricity to 
the transmission of verbal and oral messages. Telegraph 
and telephone have wrought a virtual elimination of time 
and space, and the economic importance of this revolu- 
tion is past all calculation. In telling the story of the de- 
velopment of these mechanisms and methods, therefore, 
we are obviously concerned with some of the most 
important of industrial problems; yet it is equally 
obvious that we are still in close touch with sundry 
departments of theoretical science but for which these 
practical appliances would never have been invented. 



THE DEVELOPMENT OF THE TELEGRAPH 

CURIOUSLY enough wireless telegraphy is 
the oldest form of communication by telegraph, 
as it is the most recently developed form 
by electrical means. As electricity was not discovered 
until about the beginning of the seventeenth century, 
however, it is obvious that the wireless telegraph used 
by such generals as Cyrus the Great, several centuries 
before the Christian era, could not have been by means 
of electrical apparatus. 

Nevertheless Cyrus used a form of communication 
whereby messages were sent and received through the 
air, and communications made with such rapidity that 
in a single day a message could be sent to a distance 
of thirty days' journey by horsemen — more than the 
distance across the Persian Empire. 

But Cyrus was only one of many commanders who 
used a system of signal telegraphy. Many generals and 
most nations since the beginning of history have had 
some such means, more or less definitely developed, 
for making such communication. When Napoleon was 
engaged upon his Russian campaign, Paris was kept 
constantly in touch with the movements of the French 
army by means of signals, except on those rather 

[3] 



SCIENCE IN THE INDUSTRIAL WORLD 

frequent occasions when fog or storm would interfere 
with these telegraphs. 

Such telegraphing by signals, however, was only pos- 
sible during clear weather, and as it frequently hap- 
pened that most important messages were delayed many 
days by unfavorable atmospheric conditions, attempts 
were probably made from the earliest times to discover 
some means of telegraphy whereby messages could be 
sent with certainty in daylight or in darkness regardless 
of the weather. 

FUNDAMENTAL DISCOVERIES 

The discovery of electricity, or rather a discovery by 
Stephen Gray that electricity could be conducted prac- 
tically unlimited distances by means of wires or threads, 
made possible the modern telegraph. But several 
discoveries as to the properties and possibilities of elec- 
tricity were necessary, after Gray's initial discovery, 
before telegraphy in practical form was possible. The 
principles involved in these discoveries, such as the dis- 
covery of the principle of galvanic electricity, by Gal- 
vani, the close association between electricity and magne- 
tism by Oersted, and the principle of electromagnetic 
induction by Michael Faraday, have been fully described 
in a preceding volume of this series dealing with the 
history of scientific principles, and need only be referred 
to here in direct connection with certain discoveries; 
and for full descriptions of them the reader is referred to 
earlier volumes of the series. 

Although Stephen Gray made the discovery that 

[4] 



DEVELOPMENT OF THE TELEGRAPH 

communication could be made by electricity over several 
hundred feet of wire or cord, the thought of utilizing 
this discovery as a means of communication seems 
not to have occurred to him. His discoveries were made 
in 1729, but it was something like a quarter of a century 
later before any definite attempts were made to utilize 
these discoveries in telegraphy. It is probable that the 
idea of doing such a thing had occurred to many ex- 
perimenters before that time, but if so their ideas had 
not been recorded; and the first proposal for employ- 
ing electricity in this manner seems to have been made 
by a person who signed himself "CM." in a short 
article which appeared in Scots' Magazine, Edinburgh, 
for Feb. 17, 1753. In this, as will be seen in the follow- 
ing quotation, the author had developed the idea cover- 
ing the underlying principles of electric telegraphy. 
This communication was the following: 

"Sir: — It is well known to all who are conversant 
in electrical experiments, that the electric power may 
be propagated along a small wire, from one place to 
another, without being sensibly abated by the length of 
its progress. Let, then, a set of wires, equal in number 
to the letters of the alphabet, be extended horizontally 
between two given places, parallel to one another, 
and each of them about an inch distant from that next 
to it. At every twenty yards' end, let them be fixed in 
glass, or jeweller's cement, to some firm body, both to 
prevent them from touching the earth, or any other non- 
electric, and from breaking by their own gravity. Let 
the electric gun-barrel be placed at right angles with the 

[s] 



SCIENCE IN THE INDUSTRIAL WORLD 

extremities of the wires, and about an inch below them. 
Also let the wires be fixed in a solid piece of glass, at 
six inches from the end ; and let that part of them which 
reaches from the glass to the machine have sufficient 
spring and stiffness to recover its situation after having 
been brought in contact with the barrel. Close by the 
supporting glass, let a ball be suspended from every 
wire; and about a sixth or an eighth of an inch below 
the balls, place the letters of the alphabet, marked on 
bits of paper or any other substance that may be light 
enough to rise to the electrified ball; and at the same 
time let it be so contrived, that each of them may re- 
assume its proper place when dropped. 

"All things constructed as above, and the minute 
previously fixed, I begin the conversation with my dis- 
tant friend in this manner: Having set the electrical 
machine a-going as in ordinary experiments, suppose I 
am to pronounce the word Sir; with a piece of glass, 
or any other electric per se, I strike the wire S y so as to 
bring it in contact with the barrel, then /, then R, all in 
the same way: and my correspondent, almost in the 
same instant, observes these several characters rise in 
order to the electrified balls at his end of the wires. 
Thus I spell away as long as I think fit; and my cor- 
respondent, for the sake of memory, writes the charac- 
ters as they rise, and may join and read them afterwards 
as often as he inclines. Upon a signal given, or from 
choice, I stop the machine ; and, taking up my pen in my 
turn, I write down whatever my friend at the other end 
strikes out. 

"If anybody should think this way tiresome, let him, 

[6] 



DEVELOPMENT OF THE TELEGRAPH 

instead of the balls, suspend a range of bells from the 
roof, equal in number to the letters of the alphabet; 
gradually decreasing in size from the bell A to Z; and 
from the horizontal wires let there be another set reach- 
ing to the several bells; one, viz., from the horizontal 
wire A-to the bell A, another from the horizontal wire B 
to the bell B, etc. Then let him who begins the dis- 
course bring the wires in contact with the barrel, as 
before; and the electrical spark, breaking on bells of 
different size, will inform his correspondent by the sound 
what wires have been touched. And thus, by some 
practice, they may come to understand the language of 
the chimes in whole words, without being put to the 
trouble of noting down every letter. 

"The same thing may be otherwise effected. Let the 
balls be suspended over the characters as before, but 
instead of bringing the ends of the horizontal wires in 
contact with the barrel, let a second set reach from the 
electrified cake, so as to be in contact with the horizontal 
ones; and let it be so contrived, at the same time, that 
any of them may be removed from its corresponding 
horizontal by the slightest touch, and may bring itself 
again into contact when left at liberty. This may be 
done by the help of a small spring and slider, or twenty 
other methods, which the least ingenuity will discover. 
In this way the characters will always adhere to the 
balls, excepting when any one of these secondaries is 
removed from contact with its horizontal, and then the 
letter at the other end of the horizontal will immediately 
drop from its ball. But I mention this only by way of 
variety. 

[73 



SCIENCE IN THE INDUSTRIAL WORLD 

"Some may, perhaps, think that although the elec- 
tric fire has not been observed to diminish sensibly in its 
progress through any length of wire that has been tried 
hitherto, yet as that has never exceeded some thirty 
or forty yards, it may be reasonably supposed that in a 
far greater length it would be remarkably diminished, 
and probably would be entirely drained off in a few miles 
by the surrounding air. 

"To prevent this objection, and save longer argu- 
ment, lay over the wires from one end to the other with 
a thin coat of jeweller's cement. This may be done for 
a trifle of additional expense, and, as it is an electric 
per se, will effectually secure any part of the fire from 
mixing with the atmosphere. I am, etc., CM." 

EARLY EXPERIMENTS 

Following this proposal, various telegraphs were in- 
vented, most of them too complicated or too visionary 
to be of any possible practical importance. Galvanic 
electricity had not as yet been discovered and the static 
electricity then available was most erratic and uncertain 
in its action. Nevertheless by the end of the century, 
the time of the discovery of galvanism, such progress had 
been made by numerous inventors that an electric 
telegraph, fulfilling at least one of the essential condi- 
tions, that of being capable of transmitting definite 
messages, had been devised. Of the various ones that 
of the Spaniard, Don Francisco Salva, who announced 
his invention to the Academy of Science of Barcelona 
in December 1795, was perhaps the most important and 
interesting. 

[8] 



DEVELOPMENT OF THE TELEGRAPH 

Salva pointed out that if double wires were laid from 
the city of Barcelona to Mataro, and a man at Mataro 
should hold the ends, he could be given a shock from a 
Leyden jar from the Barcelona end, and messages pre- 
viously determined communicated to him. But such 
simple signaling would not suffice, as any telegraph to be 
practical must be able to send communications of every 
kind, and this, Salva thought, could be done with no 
great difficulty. 

With eighteen letters every word in the language may 
be expressed. Thus by having eighteen or twenty 
wires, and a corresponding number of Leyden jars, 
with a man holding each jar and representing a letter of 
the alphabet, it would be possible to communicate 
definite messages to a distant city. This, of course, 
could be simplified, and Salva suggested that by reduc- 
ing the number of men to six or even less, each man 
interpreting three or more signals as certain letters, 
definite messages could be sent. 

But as even this number of wires, no matter how high 
they might be mounted above the ground, would be 
likely to be injured, Salva suggested insulating them 
and putting them into a single cable. He even went 
further than this and suggested the submarine use of 
the cable — probably the first suggestion of this kind re- 
corded. In this suggestion the double wire was to be dis- 
pensed with, the water being used for the return circuit. 

Shortly after the time of Salva's telegraph a French- 
man by the name of Alexandre seems to have perfected a 
practical telegraph which worked on the principle of an 
indicator that pointed to the letters marked on a dial 

[9] 



SCIENCE IN THE INDUSTRIAL WORLD 

when such letters were indicated by a similar pointer on 
a corresponding dial, the two being connected by wires. 
Alexandre, realizing the importance and possibilities of 
his invention, kept the method by which these mysterious 
indicators were made to transmit messages a closely 
guarded secret, although he was constantly exhibiting 
the practical workings of his device. 

Many of the leading philosophers who witnessed these 
exhibitions were convinced of the practicality of this 
telegraph, and it is possible that had Alexandre been 
willing to impart his secret to certain savants who were 
appointed by Napoleon to examine into the merits of the 
inventor's claims, his telegraph would have been put to 
practical use. Alexandre obstinately refused to reveal 
his secret, however, except to the First Consul in person 
and alone; but his request for such an interview, in 
which he promised that in ten minutes he could reveal 
the entire secret because of its simplicity, was never 
granted. Napoleon was unmistakably interested, so 
much so in fact that he requested the great scientist, 
Delambre, to investigate Alexandre's telegraph and 
report on the matter to him. Delambre did so, and his 
report, although made with scientific caution, was on 
the whole favorable. But inasmuch as he was obliged 
to judge of the merit of the telegraph by casual obser- 
vation of its workings, without even being allowed to 
know whether it was electricity or some other force that 
actuated the indicators of the dial, he, in his official 
report to the First Consul, so carefully guarded every 
statement that Napoleon paid no more attention to the 
invention. 

hoi 



DEVELOPMENT OF THE TELEGRAPH 

It was a most unfortunate thing, particularly for 
Alexandre himself, that he was so secretive in regard to 
his invention. Had he made known this to Delambre, 
a man in whom he might have placed implicit trust, his 
desired interview with Napoleon would undoubtedly 
have been granted, and, in view of the enthusiasm and 
generosity of the French Emperor toward successful 
inventors, it is possible that Alexandre would have 
lived as a famous and opulent scientist, instead of an 
obscure, impoverished, and unhappy "crank." 

GALVANISM GIVES A NEW STIMULUS TO INVENTORS 

Alexandre's invention was undoubtedly made to 
operate by the agency of static or frictional electricity, 
inasmuch as galvanic electricity had only just been dis- 
covered at that time. But shortly after this the invention 
of the "voltaic column" gave a fresh stimulus to in- 
ventors who were attempting to perfect the telegraph. 
One of the first applications of this invention of Volta's 
was by the same Spaniard, Salva, referred to a moment 
ago, about 1804; but a more successful attempt was 
made by the Bavarian Sommerring, who utilized with 
this invention the discovery of Nicholson and Carlisle 
that a galvanic current would decompose chemicals in 
solution. 

It had been found by these two scientists that if two 
points of metal were immersed in water and connected 
with a galvanic cell, the water would be decomposed 
into its elements, oxygen and hydrogen, by the action 
of electricity, this decomposition being indicated by 

En] 



SCIENCE IN THE INDUSTRIAL WORLD 

small bubbles which were given off at the two points of 
metal in the fluid. Streams of these bubbles appeared 
at these points as soon as the current was turned on, 
ceasing as soon as it was turned off. In other words, the 
closing and opening of the circuit could be detected 
almost instantly by observing the bubbles given off by 
the metal points. This discovery of the action of a 
galvanic current was at once utilized by Sommerring to 
produce a semi-practical telegraph. 

Sommerring's first invention was made with a glass 
jar containing acidulated water into which protruded 
five metal points. Each of these points was connected 
with a voltaic battery by wires so arranged that when any 
two of them were touched with a metal handle made for 
the purpose, a circuit was completed and bubbles of 
gas were given off from the two corresponding metal 
points in the water. By including a certain number of 
wires or points, or by working a definite number in 
combination, messages could be sent by this chemical 
telegraph. 

Sommerring, continuing his experiment, finally ar- 
ranged a sort of code whereby telegraphic signals could 
be sent and interpreted by a process considerably sim- 
plified over the original form. His simplest telegraph, 
however, was one in which each of the letters of the 
alphabet was represented by a metal point in the glass 
jar containing the fluid. At the base of each point the 
letter was marked so that it could be read instantly by 
the receiver. In this way a simple stream of bubbles 
given off by a metal point indicated that a certain 
letter was to be used in making up the words of the 

[12] 



DEVELOPMENT OF THE TELEGRAPH 

message. Such an arrangement necessitated the use of 
at least twenty-five wires, one practically for each letter 
and one extra for the return current, and was, of course, 
impracticable. 

One of the most ingenious things about this chemical 
telegraph was an arrangement whereby the attention of 
the receiving operator could be attracted at any time. 
The sending operator could ring a bell of the receiving 
machine by simply pressing a button which closed one 
of the circuits for a few seconds. It was so arranged that 
the bubbles of gas produced at the metal point of this 
particular circuit accumulated under an inverted cup 
attached to a lever and immersed in the fluid of the re- 
ceiving apparatus. The accumulation of gas naturally 
caused the cup to rise toward the surface, and lifting at 
the same time the lever, it released a small leaden ball 
which fell upon the alarm bell and attracted the opera- 
tor's attention. 

The objection to this form of telegraph, or at least 
the most vital objection, lay in the fact that such a great 
number of wires were required in its operation. These 
wires were arranged by Sommerring in the form of a 
cable, but this of course was very expensive and dif- 
ficult to repair when injured. An improvement over 
Sommerring' s device was what is known as Schweigger's 
telegraph, constructed on the same principle, but with 
the number of wires reduced to two. In using this 
telegraph a signal code was of course necessary, but 
this requisite was also carefully worked out by Schweig- 
ger. In actual practice, however, neither of these tele- 
graphs was of sufficient value to make them of any 

[13] 



SCIENCE IN THE INDUSTRIAL WORLD 

commercial importance, although in the mere matter of 
signaling messages they were practical telegraphs. 

ELECTRO-MAGNETISM GIVES NEW CLUES 

In 1815, the revolutionary discovery of Oersted that 
a magnetic needle could be deflected by the passage of a 
current of electricity through a wire extended longi- 
tudinally over the needle, marked an epoch in the de- 
velopment of electrical telegraphy. From that moment 
the practical telegraph became possible, although it was 
two decades later before the actual working telegraph 
came into commercial use. In this connection it should 
be remembered that the telegraph as referred to here is 
the one in ordinary commercial use. Means of com- 
municating and signaling at certain distances and for 
special purposes were employed in laboratories and in a 
small way by various investigators fully half a century 
before the perfection of the commercial telegraph. And 
while these early devices are interesting as recording 
experimental phases of the development of the modern 
telegraph, they must not be confused with the practical 
instruments finally perfected by Morse any more than 
the "wireless telegraph" of Cyrus the Great should be 
confused with the wireless telegraph of Marconi or other 
recent inventors. 

Probably the first telegraph apparatus utilizing the 
discovery of Oersted was made by Baron Schilling, a 
Russian. While acting as an attache to the Russian 
embassy at Munich, in 18 10, Schilling had been much 
interested in one of Sommerring's discoveries exhibited 
in that city. He at once began making experiments in 

[14] 



DEVELOPMENT OF THE TELEGRAPH 

telegraphy, and, becoming familiar with Oersted's 
discovery a few years later, invented a telegraph and 
formulated a code whereby messages could be read from 
a needle moving right and left as the current passed 
through a coil surrounding it. This telegraph, which 
was first made in 1825, aroused great popular interest, 
and Schilling received the support of some of the lead- 
ing men of Russia, including Czar Nicholas himself. 

One of Schilling's models of his telegraph is still in 
existence in Russia, this particular one having, in place of 
a single needle, five needles worked by five wires. It was 
this or a similar instrument, which the inventor, encour- 
aged and assisted by the great men of Russia, had brought 
to a stage of almost practical perfection when the 
experiments were cut short by his death. A vital defect 
in his system of telegraphy was the fact that the action 
of the current upon the needle at any very great dis- 
tance was weak and uncertain. 

But while Schilling, utilizing the great discovery of 
Oersted, was still experimenting with his telegraph, 
Michael Faraday had made the equally important dis- 
covery of electromagnetic induction. By this discovery, 
which was made in 1831, it was found that a piece of 
iron could be made into a magnet by winding a coil of 
insulated wire about it, and passing a current of elec- 
tricity through the coil. The magnetization could be 
produced instantaneously by closing the circuit, and 
destroyed with equal rapidity by breaking it. The 
power of such a magnet was practically unlimited, the 
number of coils about the iron proportionately increasing 
the strength of the magnet. 

[15] 



SCIENCE IN THE INDUSTRIAL WORLD 

The study of these electromagnets was taken up by 
Prof. Joseph Henry in America, who succeeded in 
producing some remarkable magnets of this type. 
One of these which he made in 1833 * s still in the pos- 
session of Yale University. It weighs about one hundred 
pounds, and was capable of sustaining a weight of 
thirty-five hundred pounds. Professor Henry was in 
the habit of giving in his class-room and at lectures 
some extremely interesting demonstrations of the power 
of his magnets. One of these was to suspend an electro- 
magnet, connected with an apparatus whereby the cur- 
rent of electricity in the surrounding coils could be 
rapidly turned on and off, from a frame. A heavy 
weight of iron, ranging from twenty-five pounds upward, 
was then attached and held in place on the under 
surface of the magnet. By setting in motion the ap- 
paratus for rapidly making and breaking the current, 
this heavy iron weight was made to perform a series of 
rebounds against the magnet with a force and sound of a 
trip-hammer, or of rapid hammering on an anvil. 

The simple explanation of this astonishing exhibition 
was that two forces, gravitation and magnetism, acted 
alternately upon the iron weight. Gravity caused it to 
fall when the current was broken, but before it could 
fall far enough to be beyond the controlling power of 
the magnet, the circuit would be again closed, causing 
the weight to fly back against the core of the magnet. 

THE FIRST PRACTICAL TELEGRAPH SYSTEM 

This discovery of the electromagnet was at once 
seized upon by inventors interested in the telegraph 

[16] 



DEVELOPMENT OF THE TELEGRAPH 

as the most probable means by which the invention 
might be perfected, and within two years after Fara- 
day's great discovery a practical working telegraph, 
the first that may properly be so termed, was invented 
by two Germans, Gauss and Weber, of Gottingen. In 
this telegraph the principle of Schilling's deflecting 
needle was combined with Faraday's principle of the 
electromagnet. The signal and receiving stations were 
connected by two lines of wires, and as early as 1833 
the two German experimenters were using this telegraph 
as a means of sending messages. 

As this first telegraph had been constructed for 
scientific rather than commercial purposes, the two in- 
ventors requested the assistance of Professor Steinheil 
of Munich in developing their discovery into practical 
form. This was done in a most ingenious manner, the 
result being a really very practical instrument for both 
sending and receiving messages; but in the meantime 
the problem had been solved in a much more simple and 
practical form in America by the man who must go 
down in history as the real father of telegraphy, Samuel 
F. B. Morse, the artist-inventor. 

The history of the attitude taken by his native country 
toward Samuel Morse affords at least one opportunity 
to refute the old proverb that a a prophet is not without 
honor save only in his own country." For after Eng- 
land had refused even to grant patents on Morse's 
invention, and France had first granted such patents 
and then appropriated them without remuneration to 
the inventor, while Russia and Germany turned a cold 
shoulder to the young American, his own country heaped 

VOL. VIII. 2 T 17 1 



SCIENCE IN THE INDUSTRIAL WORLD 

wealth and honor upon him — not, however, until he had 
toiled and suffered long. 



ANTECEDENTS AND EARLY EXPERIMENTS OF MORSE 

Morse was born at Charlestown, Massachusetts, on 
the 27th of April, 1 79 1. As a boy his tastes were for 
things artistic rather than scientific, and after attending 
Yale College for a time he became the pupil of Washing- 
ton Allston, at that time one of the leading American 
painters. In company with his teacher he went to 
Europe to study art in the schools and become familiar 
with the work of the old masters. In his work he 
obtained considerable success as a student, and his 
prospects for a successful career as a painter were 
unusually bright. 

On his return to America, in 181 5, his enthusiasm 
for art was somewhat dampened by his failure to obtain 
several important commissions for historical paintings, 
and after working at portrait painting for several 
years in Charleston, South Carolina, Washington, and 
Albany, he finally took up his residence in New York, 
where, in 1825, he laid the foundation and became the 
first president of the National Academy of Design. Two 
years later he became interested in the study of electric- 
ity, dividing his time between the study of art and in- 
vestigation of electricity. For a time, however, his 
interest in science did not replace his devotion to the 
brush; but in 1832, after returning from a trip to Europe 
undertaken with a view to further study of the old 
masters, his ardor for art, at least as a practical means 

[18] 




SAMUEL F. B. MORSE. 



DEVELOPMENT OF THE TELEGRAPH 

of earning a livelihood, was given its quietus by a 
refusal of the government to allow him to paint one of 
the great historical paintings for the rotunda of the 
Capitol at Washington. From that moment he turned 
his attention and his ambitions to the study of science, 
using art only as a means of furthering this end. 

It was on board the ship Sully, returning from his 
European trip, in 1832, that Morse first expressed the 
idea that the electric telegraph was a practical possi- 
bility. The discoveries of Faraday of the year before had 
aroused a general interest in the subject of electricity 
and particularly that of electrical communication by 
telegraph. A fellow passenger of Morse's on board 
the Sully was a certain Doctor Jackson, who was 
much interested in the possibilities of electricity and 
magnetism. During many conversations and discus- 
sions with his fellow passengers on the trip, Morse ex- 
pressed his belief that it would be possible to produce a 
telegraph by which, through the simple process of 
making and breaking a current along the wire, a code of 
signals representing the alphabet could be devised 
and turned to practical account. He not only expressed 
this belief but made sketches of electrical apparatus il- 
lustrating the principle upon which a telegraph might 
be successfully constructed. 

On reaching New York he began a series of experi- 
ments to carry out the ideas formed on shipboard. 
For four years he continued these studies, struggling in 
poverty and sometimes in actual want of food and 
clothing. By 1835 ne na d constructed a fairly success- 
ful telegraph, and had formulated a practical code for 

[19] 



SCIENCE IN THE INDUSTRIAL WORLD 

signaling and receiving messages. In these experiments, 
however, the distances to which messages could be sent 
were limited, and for a year this limitation proved a 
stumbling-block, but in 1836 he invented his system of 
"relays" for reinforcing the current at intervals along 
the line and overcoming the difficulty. 

On the second of September, of the year following 
(1837), Morse gave his first exhibition of the fruits of 
five years of labor and privation. In his little room in 
the old University building in New York he had con- 
structed a circuit of about seventeen hundred feet of 
copper wire arranged with sending and receiving in- 
struments and relays. To this room he invited a few 
of his intimate friends and there gave a practical ex- 
hibition of sending and receiving messages. The 
enthusiasm created by this demonstration led almost 
immediately to a proposition from the firm of Vail & 
Co., metal workers in New Jersey, who shortly after 
became associated with Morse in promoting and 
developing his telegraph. 

Patents were granted by the United States in 1837, 
but no action being taken at once by Congress on a 
petition which Morse made asking for an appropriation 
of funds to defray the expenses of testing the practicality 
of his invention, he sailed for Europe. It was while on 
this trip that England refused to grant him patents, and 
the other countries of Europe showed their indifference. 
Returning to America, therefore, Morse renewed his 
efforts, meeting with little success until 1843. Then 
Congress finally passed the long delayed appropriation, 
and on May 24th of the year following a telegraph from 

[20] 



DEVELOPMENT OF THE TELEGRAPH 

Baltimore to Washington was used for the first time. 
From that time forward the career of the inventor 
was a series of triumphs, marred only by one serious 
incident when Morse's claim to his invention was con- 
tested, and he was obliged to defend his position in the 
courts. 

A REGRETTABLE CONTROVERSY 

In this trial it developed among other things that 
Doctor Jackson, Morse's fellow passenger on his mo- 
mentous trip from Europe, maintained that he, and not 
Morse, was the inventor of the electrical telegraph. 
He claimed that he had explained to Morse, and had 
illustrated with sketches, a method of constructing a 
telegraph which was later usurped by Morse in his ex- 
periments. At the trial these claims were not sustained, 
but were in fact absolutely refuted by the sworn state- 
ments of those on board the boat, among these being 
the captain of the ship, who identified Morse's instru- 
ment with drawings which Morse had explained to him 
in detail on the Sully. 

Sabine, who may be taken as an impartial judge of 
this controversy, summarizes the position of Doctor 
Jackson as follows: 

" Doctor Jackson — who possesses an unenviable 
reputation in America for setting up claims to other 
people's inventions — in his statements made in 1837 
and in 1850, is guilty of considerable self-contradiction, 
and only in the latter does he even allude to the employ- 
ment of an electromagnet. Apart from this gentleman's 
equivocal character and conduct, we do not see anything 

[21] ' 



SCIENCE IN THE INDUSTRIAL WORLD 

remarkable in the fact that he should consider himself 
entitled to some participation in the credit arising 
from the invention of a telegraph in America. Two 
men came together. A seed-word, sown, perhaps, by 
some purposeless remark, took root in fertile soil. The 
one, profiting by that which he had seen and read of, 
made suggestions and gave explanations of phenomena 
and constructions only imperfectly understood by him- 
self, and entirely new to the other. The theme in- 
terested both, and became a subject of daily conversa- 
tion. Then they parted, and the one forgot or was in- 
different to the matter, whilst the other, more in earnest, 
followed it up with diligence, toiling and scheming ways 
and means to realize what had only been a dream com- 
mon to both. His labors brought him to the adoption of 
a method not discussed between them, and Morse be 
came the acknowledged inventor of a great system. 

"Fame and fortune smiling upon the inventor, it was 
natural enough that Jackson, awakening from his un- 
fortunate indolence, should remember his share in their 
earlier interchange of ideas, that had, perhaps, first 
directed Morse's attention to the subject of telegraphy. 
And, although we are compelled to pronounce dishonest 
those attempts which Jackson made to claim the later 
and proper invention of Morse — that of the electro- 
magnetic recorder — and strong as is our confidence 
in the spotless integrity of our friend, we cannot entirely 
ignore Jackson — little as he has done — nor deny him an 
inferior place amongst those men whose names are 
associated with the history and progress of the electric 
telegraph in America " l 

£223 



DEVELOPMENT OF THE TELEGRAPH 

In this connection it is interesting to note that this 
Doctor Jackson was the same man who contested 
Doctor Morton's right to the discovery of etherization. 
As with Robert Hooke, claiming other men's discoveries 
seems to have been almost a mania with him. 



PRINCIPLE OF THE MORSE TELEGRAPH 

The principle involved in the Morse telegraph is the 
same as that which was so graphically illustrated by 
Professor Henry with his magnet and falling weight 
referred to a moment ago. As illustrated by this experi- 
ment, tapping sounds could be made at any desired 
intervals by simply making and breaking a current 
conducted along a wire. If a metal hammer, or arma- 
ture, is so placed that it is held by a spring at a 
short distance above a soft-iron core around which is 
wound insulated wire connected with a galvanic battery, 
it is obvious that when the current is passing along this 
wire, making the soft iron a temporary magnet, the 
metal hammer will be drawn against this core and held 
there as long as the current is unbroken. On breaking 
the current, however, the hammer will be released and 
fly back to its original position. As this magnet can be 
made to act instantaneously and with great force, a 
sharp tapping sound will be made by the hammer as it 
snaps against the magnet when the current is closed. 

If a key so arranged that by pressing a button the 
circuit will be closed and broken when raised is placed 
somewhere along the course of the wire, the hammer or 
armature may be made to give a series of taps or blows 

[23O 



SCIENCE IN THE INDUSTRIAL WORLD 

upon the iron core or magnet corresponding precisely 
with the pressing and raising of the key-button, since 
the passage of current is practically instantaneous. If 
this button arrangement, which is called a "trans- 
mitter," is placed at some distance from the magnet and 
hammer, it is obvious that a person working the button 
of the transmitter can make certain signals to persons 
within hearing of the hammer strokes upon the magnet. 
If certain signals were mutually agreed upon, one tap 
of the hammer indicating the letter A, two taps the letter 
B, etc., messages could be sent and received with ab- 
solute accuracy. 

Such an arrangement is the underlying principle of 
the Morse telegraph, although when worked out in 
practical detail and perfected, as was done by Morse, 
the apparatus is much more complicated. Morse found, 
for example, that after a certain length of wire had been 
used the receiving instrument no longer responded to 
the making and breaking of the current. To overcome 
this he found it necessary to strengthen and increase 
the current at certain intervals with "relays," which 
were referred to a moment ago. This was one of the 
novel and important factors of his discovery. 

Another important feature was a method of recording 
the messages received other than by sight or hearing. 
Morse perfected such a recorder, by which the tappings 
of the receiving hammer were impressed upon a strip of 
paper so that an operator might interpret the message 
from the strokes and intervals of the receiver, or might 
have it as a written impression in dots and dashes on a 
strip of paper. 

[24] 



DEVELOPMENT OF THE TELEGRAPH 

The telegraph so perfected represents the practical 
telegraph of to-day. Hundreds of minor modifications 
have been made, of course, and are being made year by 
year, but the principle involved remains the same in all 
forms of the Morse telegraph, which represents at least 
ninety-five per cent, of all telegraphs the world over. In 
England for many years the needle telegraph, used by 
certain railroads, rivaled the Morse telegraph in popu- 
larity, particularly as the famous inventors, Cook and 
Wheatstone, had given great attention to that form of 
instrument. But for the last quarter of the century at 
least, there has been no rival of the Morse instrument 
that could be considered in any sense a competitor. 

MULTIPLE MESSAGES 

Early in the history of telegraphy the possibility of 
sending messages in opposite directions at the same 
time was conceived, and in 1853 an Austrian, Doctor 
Gintl, invented an instrument by which this could be 
accomplished. In this instrument a relay with coils 
wound with two separate wires was made. In one of 
these wires the current of the line batteries circulated, 
and in the other flowed a current from what is called 
an "equating" battery. These two coils, which were 
wound in opposite directions on the soft-iron cores, 
had opposite magnetic effects upon the relays when con- 
nected in the proper circuits ; so that although the whole 
circuit of one battery might pass through both relays, 
only one of them would be affected by messages coming 
from the instrument designed to affect that particular 

[25] 



SCIENCE IN THE INDUSTRIAL WORLD 

coil, the messages coming from the opposite direction 
passing through with no effect. This arrangement, with 
various modifications, came into general use shortly 
after its invention. 

A somewhat similar device, which acts upon the prin- 
ciple that currents of different intensities are not affected 
by each other, and only act upon receivers of correspond- 
ing intensity, is utilized for sending two or more messages 
in the same direction, and at the same time, on one wire. 
Supposing two sending instruments are given different 
tensions, one high and one low, and two receiving instru- 
ments are given corresponding tensions. If messages 
are sent from the high-tension transmitter, such mes- 
sages will be received by the high-tension receiver at 
the end of the wire, no effect being produced upon the 
low-tension receiver, which will be moved only upon the 
operation of the low-tension transmitter. If both 
transmitters are operated at the same time, however, 
both high- and low-tension receivers will be affected, al- 
though independently of each other. In this way it is 
possible to send two messages at the same time. 

This system is utilized also in Elisha Gray's " Har- 
monic Telegraph" for sending multiple messages. In 
this, a number of separate magnetic vibrators, which 
open and close the circuit at the rate of a certain number 
of vibrations per second, are placed in connection with 
the wire, with a corresponding vibratory receiver having 
exactly corresponding vibrational periods to each of 
the transmitting instruments. Such receivers will only 
respond to the messages sent by the transmitter of simi- 
lar vibrational period, so that no matter how many 

[26] 



DEVELOPMENT OF THE TELEGRAPH 

messages are being sent by other transmitters, each 
vibratory receiver selects its own particular message. 

Another " multiplex" arrangement is one in which a 
circle is divided into as many segments as there are 
senders and receivers, each segment being connected 
with a receiver, and a corresponding sender connected 
with the segment of a similar device at the opposite end 
of the line. A revolving " contact slider" is so arranged 
that by revolving rapidly and passing over each of these 
intervals in succession, each transmitter is allowed to 
send its message in rotation. This system, first proposed 
by Lord Kelvin, in 1858, has been developed on practical 
lines, and wires sending from four to eight separate, 
simultaneous messages are now in practical operation 
all over Europe and America. 

It was evident, even in the early days of electric teleg- 
raphy, that messages could be sent and received by 
the instruments much more rapidly than the keys could 
be worked by hand, and automatic transmitters and 
receivers were soon invented. As early as 1846, Bain 
invented a method of sending such messages automat- 
ically, but an apparatus on similar principles was later 
devised by Professor Wheatstone, which, with various 
modifications, still remains in use. In this arrange- 
ment the message to be sent is recorded by means of 
punched holes on a strip of paper. When this strip is 
passed through the transmitter, these holes cause the 
automatic transmission of the message, which is recorded 
at the other end of the line. In this way five or six 
hundred letters or more can be sent in a minute. This 
system, with the various modifications of it, is partial- 

[27] 



SCIENCE IN THE INDUSTRIAL WORLD 

larly useful where the same messages are to be sent to a 
number of different places, as the perforated strip of 
paper can be made in multiples at a single punching. 

Many different types of telegraph recorders have 
been invented since the time of Morse's first instrument, 
several of these being the experimental inventions of 
Morse himself. The principles involved in these 
recorders have been both chemical and mechanical, the 
mechanical ones, as a rule, predominating. Practical 
chemical recorders are used, however, utilizing the 
well-known fact of chemical decomposition by the 
electric current. For example, if a strip of paper is 
saturated with some chemical which is easily decom- 
posed by electricity, and in this decomposition changes 
color, the pressure of an electrical needle upon this strip 
of paper will produce a mark. If the strip is arranged 
on rolls which pass it beneath the position of the needle 
at a uniform rate of speed, dashes and dots may be 
made by the needle's contact with the paper for a 
longer or shorter time. This method is found to be 
entirely practical, and the principle is utilized in many 
recording devices. 

It is quite beyond the scope of this work to go into 
details of the hundreds of telegraphic devices, for signal- 
ing, etc., the numbers of which are being multiplied al- 
most daily, and which have become practical necessi- 
ties in civilized communities. But it is interesting 
to remember that such widely divergent mechanisms as 
the dial-signaling apparatus with which the captain of 
the ocean liner communicates his commands to the 
engineer far below in the engine-room, the Atlantic 

[*8] 



DEVELOPMENT OF THE TELEGRAPH 

cable with which Europe communicates instantly with 
America, the button that explodes a submarine mine, 
and the familiar electric door- bell and call-button, are 
all developments of Morse's practical application of 
Michael Faraday's discovery of electromagnetic in- 
duction. 



[29] 



II 

THE SUBMARINE CABLE 

THE story of Robert Bruce and the spider, and 
the story of Bruces' own perseverance and per- 
sistence in the face of adversity, have become 
classic ; but in recent years Bruce' s traditional efforts have 
been equaled, if not eclipsed, by the persistent efforts and 
unwavering faith of the handful of men who projected and 
finally perfected the Atlantic cable. Bruce, fighting on 
the defensive, had conditions forced upon him; but the 
heroes of the Atlantic cable not only took the initiative 
but were obliged to keep it in the face of most discourag- 
ing public sentiment, financial difficulties, and worst 
of all, the bare fact that attempt after attempt proved 
unsuccessful. Contending against defects in the cable 
structure, broken cables, cables fouled and destroyed 
by vessels before they could be laid; and finally, after 
heartbreaking efforts, when a cable was successfully 
laid across the Atlantic, to have it "burned out" and 
destroyed by an electrician — all this makes a story 
rivaling the most vivid imaginings of the novelist. 
Happily, like the endings of most novels, the last word 
of this story is a complete triumph for the heroes of the 
plot; and the names of Cyrus W. Field, Sir Charles 
Bright, John W. Brett, and Lord Kelvin, must go 
down in history as having accomplished one of the 

[30] 



THE SUBMARINE CABLE 

most difficult feats in history, as well as one of the most 
useful commercial and economic ones. 

The Atlantic cable was not the first submarine 
telegraphic communication ever projected or accom- 
plished. As early as 1838, a successful cable had been 
laid across the Hugh River in India, and in 1842, 
Morse had laid a similar cable in New York Harbor. 
The great difficulty with these first cables was the fact 
that effective and permanent methods of insulating had 
not yet been discovered. Copper wire wound with 
strings saturated with tar, wax, and pitch, acted well 
enough for a short time at small distances, but it was 
not until the discovery that gutta-percha makes an 
almost ideal insulator, that submarine cables of any 
length became possible. With this discovery, however, 
a great impetus was given to cable-laying, and in 1845 
a company was formed for laying a cable between 
England and France, a distance of twenty-five nautical 
miles. 

ENGLAND LINKED WITH THE CONTINENT 

The announcement of a company for such a purpose 
was received in a manner quite beyond the compre- 
hension of the people of the present generation, surfeited 
as they are with the marvelous accomplishments of ap- 
plied science, which sends messages through the air, 
photographs through opaque substances, and performs 
numerous other seemingly miraculous feats inconceiv- 
able to the most imaginative persons of two generations 
ago. Few people, either in England or France in 1845, 

[31] 



SCIENCE IN THE INDUSTRIAL WORLD 

believed that the Channel cable could succeed. Those 
of a suspicious nature denounced the scheme as a gigantic 
swindle; others derided it as a mad freak of the im- 
agination of enthusiastic visionaries; while one critic 
naively pointed out that the scheme was impossible on 
account of the roughness of the Channel bed, believing 
that the intended method of communication was that of 
actually pulling upon the cable, like pulling a mechanical 
house-bell worked by wires. 

Nevertheless the projectors completed and laid their 
cable, and communications were made between England 
and France. A message of congratulation was sent to 
Louis Philippe, and public incredulity had just turned 
into public rejoicing when suddenly the cable ceased 
to work. It was learned afterward that a Boulogne 
fisherman, hooking up the cable and being unable to 
account for such a mysterious-looking "seaweed," had 
hacked off a section to take home to show his friends. 

The cable of 1846 proved conclusively that, for short 
distances at least, the submarine telegraph was a possi- 
bility. But sending a message twenty-five miles through 
a cable laid in comparatively shallow water is a different 
matter from sending it two thousand miles submerged 
in water two miles in depth. Cables insulated with 
gutta-percha did not conduct the current as readily as did 
cables of the same size without insulation and sus- 
pended in the air, the gutta-percha tending to absorb 
and retard part of the charge. This difficulty, however, 
was soon overcome by means of a succession of opposite 
currents, but the problem that could not be solved ex- 
cept by actual experiment was the effect that might be 

[32] 



THE SUBMARINE CABLE 

produced upon the cable itself or upon the electric 
current by the great pressure of the water at ocean 
depths. 

CYRUS FIELD PROJECTS THE ATLANTIC CABLE 

But now a man of business, and not a scientist, be- 
came interested in the possibility of cable communica- 
tion across the Atlantic. This was Cyrus W. Field, an 
American business man who had made a fortune and 
retired before he had reached forty years of age. Be- 
coming greatly interested in the attempts at cable -laying 
in Europe, he crossed the Atlantic and in 1856 suc- 
ceeded in forming the Atlantic Telegraph Company, 
capitalized at £350,000. Of this amount Field reserved 
£75,000 in shares for his own placing in America; but 
while the English capital was quickly subscribed, little 
response was given in America, less than one-twelfth 
of the £75,000 being taken up. 

Among the scientific men of this company was the late 
Lord Kelvin, to whose unwavering faith in the possi- 
bility of transatlantic communication, scientific and 
practical advice, and invention of several marvelous 
instruments, the ultimate success of cable-laying is in 
large measure due. For his views were in opposition to 
many of the leading scientists of the time, many of them 
much better known than the young Scotch professor. 

One instance may be cited as showing how the purely 
theoretical scientist is perennially bobbing up and 
"proving conclusively" with theories and dogmas that 
certain things are impossible, only to have them shown to 
be perfectly practicable by actual demonstrations. On 

VOL.VIII.-3 [33] 



SCIENCE IN THE INDUSTRIAL WORLD 

the announcement of the formation of this company 
for telegraphing across the Atlantic, Sir G. B. Airy, 
F.R.S., Astronomer Royal of England, declared that 
such means of communication was impossible; first, 
because it was a physical impossibility to submerge a 
cable safely to so great a depth, and secondly, that no 
signals could travel for such a distance, anyway. Know- 
ing the type of mind of this kind of scientist, it is probable 
that long after the Atlantic cable was an accomplished 
fact, the Astronomer Royal was still maintaining that 
the thing was impossible, and showing his mathematical 
calculations to prove it. Fortunately for civilization 
Sir Charles Bright and Lord Kelvin were scientists of a 
different type. 

With the fund subscribed, the making of a cable was 
begun at once, and while this was in progress certain 
ships detailed for the purpose were being prepared to 
receive the cable, and fitted out with apparatus for 
laying it. The total space occupied by the cable was 
too great for any single vessel, there being some 340,500 
miles of copper wire alone used in its construction. The 
English government, therefore, detailed the war-ship 
Agamemnon, and the United States government sent 
over the Niagara. Into the holds of these ships the 
cable was coiled in great tanks, each coil carefully laid 
by hand so that it would uncoil readily and without any 
possibility of even a momentary hitch which might prove 
disastrous to the undertaking. The Niagara was to 
undertake to lay the European half of the cable, the 
Agamemnon taking up the task in mid-ocean and con- 
tinuing the work as far as the American shore. 

[34] 



THE SUBMARINE CABLE 

HIGH HOPES — AND FAILURE 

By the time the two cable vessels and their fleet of 
consorts were ready to start, great enthusiasm and faith 
in the success of the project had been created both in 
America and Europe, and great personages of the 
British Empire gathered on shore at the starting point to 
God-speed the two vessels on their momentous voyage. 
This starting point was in Valentia Bay, Ireland; and 
amid tooting whistles and flying bunting the Niagara 
began paying out the cable. But the start was unpropi- 
tious, the paying-out machinery not working well, and 
five miles from shore the cable parted. This was not a 
serious matter in that depth of water, however, and the 
ends of the cable were soon spliced, the paying-out 
machinery adjusted, and the Niagara once more 
resumed her voyage. 

The heartbreaking suspense of the promoters on 
board the fleet of cable-boats may be readily imagined. 
Hour after hour, and mile after mile, the threadlike line 
of wire must keep dropping continuously from the stern 
of the ship, must be regulated so that it did not run out 
too fast and yet not restrained with sufficient force to 
break it. Not once must the boat, or the machinery for 
paying out, stop after deep water was reached, as the 
weight of the cable would cause it to break if checked 
even momentarily. 

As the Niagara continued successfully to pay out the 
cable hour by hour, however, the promoters breathed 
more easily, and the messages and communications 
which were being constantly sent from ship to shore in 

[35] 



SCIENCE IN THE INDUSTRIAL WORLD 

order to test the cable, were supplemented by cheerful 
messages from the officers to friends on land, and to 
friends in America, by way of outgoing vessels from 
England. 

The unknown effects of the deep-sea pressure were 
tested and found not to interfere with the working of the 
cable on the third day of the voyage when the deep 
ocean was reached, and the cable continued to work 
uninterruptedly. With this bugaboo safely behind them 
the spirits of all concerned reacted and mounted to the 
highest pitch of anticipation. The third day passed and 
all was going well. The fourth bade fair to be a repeti- 
tion of the third, when suddenly, without a moment's 
warning, the cable parted and sank. 

The cause of the accident was the failure to release 
the brakes of the paying-out machine at a critical 
moment — a turn of a hand-wheel in the wrong direc- 
tion by an over-anxious workman — with the result that 
a fortune in money was lost and the hopes of two con- 
tinents shattered. The manipulation of this vital part of 
the cable machinery had been undertaken by Charles 
Bright in person, who had stood by the machine most of 
the time, day and night, since the beginning of the trip. 
But having occasion to step forward to see how the cable 
was coming out of the hold, he left the paying-out 
machine for a moment in charge of a mechanic, a man 
perfectly familiar with the construction and running 
of it. Bright had hardly left his place, however, when 
he heard the machinery stop. Rushing back he 
called to the mechanic to release the brakes; but in 
the crucial moment of excitement the man turned 

[36] 



THE SUBMARINE CABLE 

the release wheel the wrong way, and the cable snapped 
at once. 

The high character of Bright is shown in the matter 
of his official report of this unfortunate accident to the 
company. One can imagine what his feelings must have 
been toward the man whose mistake meant so much to 
him, for Bright's heart and soul were in the enter- 
prise. But in this report, far from naming the man 
or blaming him, he simply says, "On examining 
the machine I found that the brakes had not been 
released, and to this, or to the hand-wheel of the brake 
being turned the wrong way, may be attributed the stop- 
page and consequent fracture of the cable. " It is 
gratifying to know that the man who could thus restrain 
his feelings was destined finally to succeed in this and 
many other great undertakings. 

It was a sad spectacle presented by the "Wire Squad- 
ron" a few days later as it crept back into harbor, 
defeated, and disgraced in the eyes of the critics. No 
enthusiastic well-wishers gathered there to encourage 
it. Gloom was everywhere — except in the hearts of the 
"I told you so" croaking critics. Gloom and depres- 
sion — but not dejection, at least in the camp of the pro- 
moters and stockholders; for money was subscribed, 
and seven hundred miles more cable ordered made at 
once. 

A SECOND FIASCO 

The experiences of the first attempt were profited by, 
and, among other important innovations, a self -releasing 
brake was devised by Bright and a Mr. Amos which 

[37] 



SCIENCE IN THE INDUSTRIAL WORLD 

overcame the possibility of a repetition of the accidental 
breaking of the cable by the paying-out machinery. 
Another great invention, made by the moving scientific 
spirit of the enterprise, Professor Thomson (afterward 
Lord Kelvin), was that of his mirror-speaking instrument, 
or "marine galvanometer," which eventually revolu- 
tionized long-distance electric signaling and testing on 
shipboard. This instrument consisted of a tiny magnet 
and a reflector, weighing together about a grain, with 
which transmitted messages were magnified by reflected 
light, so that the faintest current could be detected and 
signals interpreted. 

Early in 1858, the new cable being completed, a second 
attempt was made. This time, however, a new plan was 
adopted, and instead of beginning the cable-laying 
from one end, both ships, the same Agamemnon and 
Niagara as before, proceeded to a point in mid-ocean, 
spliced the two ends of the cable together, and headed 
in opposite directions paying out the cable as they went. 
When three miles apart the cable broke by becoming en- 
tangled in the machinery of the Niagara. Both ships 
at once put about, a new splice was made, and again 
they headed for opposite shores. All went well for a 
few hours when the cable again parted — this time ap- 
parently somewhere at the bottom of the ocean. Again 
both boats put about, returned to the rendezvous, and 
spliced the cable for a third time. 

This time things looked more hopeful, and mile after 
mile of cable was laid, everything moving smoothly. 
Something over a hundred miles had been reeled off by 
each ship — a total of two hundred and twenty- three 

[38] 



THE SUBMARINE CABLE 

miles of the wire strand— when suddenly, without any 
warning, the cable again parted. As signals could not 
be exchanged between the ships, there was nothing 
for it but to relinquish the undertaking and return to 
Queenstown as agreed upon before starting. 

SUCCESS AT LAST 

The meeting of the board of directors of the Cable 
Company was a gloomy affair. The chairman probably 
voiced the feelings of a large share of the members when 
he suggested that the cable remaining on shipboard be 
sold as junk to the highest bidder, or words to that effect. 
But Cyrus Field was there, and Bright, and Brett, and 
with them the indomitable Professor Thomson and Cur- 
tis Lampson. And once more the indomitable "Wire 
Squadron" was ordered to sea. 

There was no pomp and display in this departure. 
The ships crept out of the harbor more like sea-wolves 
departing after an unsuccessful raid — a handful of ships 
carrying a party of cracked-brained visionaries, to whom 
two tolerant governments had generously loaned their 
vessels. This was on Saturday, July 17, 1858, and it is 
probable that few persons, either in Great Britain or in 
America, aside from immediate friends and relatives 
of the members of the expedition, gave a single thought 
to the movements of the boats or knew or cared what 
they might be doing. 

But on August 5th, the world was awakened from its 
lethargy with a start. A message had been flashed from 
Valentia to the Board in London. "The Agamemnon 
has arrived at Valentia, ,, it read, "and we are about to 

[39] 



SCIENCE IN THE INDUSTRIAL WORLD 

land the end of the cable. The Niagara is in Trinity 
Bay, Newfoundland. There are good signals between 
the ships." It was from Charles Bright (made Sir 
Charles a few days later), announcing that the Eastern 
and Western hemispheres were no longer separated by 
weeks, but only by seconds. 

England received the news with the unbounded en- 
thusiasm that can only come with complete surprise, or 
after intense expectancy. " The rejoicings in America,' ' 
says The Times, "both in public and private, knew no 
bounds. The astonishing news of the success of this 
unparalleled enterprise, after such combats with storm 
and sea, created universal enthusiasm, exaltation, and 
joy, such as news perhaps never before produced by 
any event, not even the discovery of the Western hemi- 
sphere." l 

Congratulatory and commercial messages were soon 
being sent and received, and people of both hemispheres 
were becoming accustomed to receiving news every 
morning which two months before must have been two 
weeks old at least, when on October 20th, after a total 
of 732 messages had been sent across the ocean, the 
cable ceased to work. The knowledge of the electrician 
had not kept pace with the engineer, and the destruction 
of the cable had resulted from too strong and misap- 
plied currents. 

IMPROVED METHODS AND NEW CABLES 

The depression following this catastrophe, however, 
^as not to be compared with that following some of the 
earlier ones. A successful cable had been laid and oper- 

[40] 



THE SUBMARINE CABLE 

ated, and even the most short-sighted could see that the 
scheme was no longer impossible or visionary. But 
would a cable ever pay? That was the vital question. 
Cyrus Field thought it would, and his associates agreed 
with him. Meanwhile shorter cables were being laid in 
the Mediterranean Sea, the Red Sea, and other places, 
and both engineer and electrician were perfecting their 
knowledge of cables and cable instruments. The Civil 
War in America for a time diverted the efforts of the 
cable company from attempting another transatlantic 
cable. By the time of the close of the war, however, 
in 1865, methods of cable-making, cable-laying, and 
cable instruments had been so greatly improved that 
the promoters of the original company had come to have 
very great confidence in their project, and this feeling 
was shared by many promoters, as shown by the fact 
that other companies had been formed for the same 
purpose. 

In 1865, therefore, the attempt to lay a cable across 
the Atlantic was renewed. This cable differed con- 
siderably in construction from the original one. It was 
one and one-tenth inches in diameter and weighed 
thirty-six hundred pounds per mile in the air, but only 
fourteen hundred pounds in water. There had been so 
many obvious disadvantages in the method of laying 
the cable in sections by two ships that it was decided, 
if possible, to have a single ship, carrying all the cable, 
lay it directly from shore to shore — if a ship large enough 
to carry the enormous weight of the new cable could be 
found. 

The ideal ship for this purpose was at that moment 

[41] 



SCIENCE IN THE INDUSTRIAL WORLD 

lying idle at her dock because she had not proved a 
commercial success. This was the Great Eastern, the 
monster vessel of 22,500 tons displacement, which had 
been completed in 1858, half a century in advance of her 
time. She was propelled both by paddle-wheels and 
propeller, and her enormous size and corresponding 
steadiness made her an ideal boat for cable-laying. 
The new cable was therefore stored aboard and the 
laying commenced. On this voyage the tireless promoter 
Field and the scientist Sir William Thomson were 
aboard with many others either directly or indirectly 
connected with the enterprise. 

The advance that had been made in cable-laying 
since the achievement of 1858 was shown in many 
ways on this voyage. For example, if a fault was dis- 
covered in the cable after it had been dropped overboard, 
it was now possible to reverse the machinery, pick up 
the cable to the point at which the fault occurred and 
repair it. This was necessary on one occasion when 
the fault had been passed ten miles before discovery, 
but this was accomplished successfully and with no 
very great difficulty. After laying 11 86 miles of cable, 
however, and when the end of the voyage was almost 
in sight, the cable parted and could not be recovered. 
Picking-up machinery had been carried by the boat for 
just such an emergency, but this machinery was not 
effective, although the cable was grappled and raised 
part way to the surface several times. The attempt to 
complete the laying was therefore abandoned for the 
moment. 

By the middle of the following year, however, new 

[42] 



THE SUBMARINE CABLE 

and better picking-up machinery had been devised, 
and on June 30, 1866, the Great Eastern again started 
laying another cable. Fourteen days later her work 
was completed successfully, and communication between 
the continents began at once. Not satisfied with this 
success, the great ship returned to the scene of her 
mishap of the preceding summer, and after overcoming 
many difficulties succeeded in grappling the broken 
end of the cable of '65, spliced it to a new cable, and 
completed the second workable cable within a few 
weeks after the completion of the first. 

This was about the first and last useful work of any 
kind ever accomplished by the Great Eastern. It was 
perhaps enough for any one vessel to have accomplished 
the "greatest undertaking of the century." But this un- 
dertaking was the only useful purpose to which the boat 
could be put, and a few years later she was broken up. 

Since the completion of the 1866 cable great advances 
have been made in all phases of submarine telegraphy. 
At present the total number of miles of such cables is 
considerably over two hundred thousand, their cost 
being from one thousand to fifteen hundred dollars per 
nautical mile. The most expensive single item of ex- 
pense in these cables is the cost of the gutta-percha 
used, but as nothing less expensive has been found to 
replace it, this great cost is unavoidable. 

Obviously with these two hundred thousand and more 
miles of cable, repairs are constantly necessary. But 
repairing submarine cables to-day is not the onerous 
task that it was in the early days of cable-laying. When 
a fault or fracture occurs at the present time, it is possible 

[43] 



SCIENCE IN THE INDUSTRIAL WORLD 

to determine approximately the position of the fracture 
by electrical tests from the shore. The repair ship is 
then sent to the point indicated and the cable raised and 
repaired. In order to raise the strand the ship drags 
the bottom transversely with a five-or six-pronged anchor, 
or grapple, a dynamometer indicating when the cable 
has been caught. 

In very deep water, unless the cable has been hooked 
near the broken end, the raising of it directly to the sur- 
face would cause so great a strain that another fracture 
would probably result. To obviate this it is raised a 
certain distance, perhaps half-way to the surface, and 
then held in position by a buoy attached to the grapple 
rope. At some little distance from this point the cable 
is again hooked with another grapple iron, and unless 
the depth be extreme, may now be brought directly to 
the surface, as sufficient weight is relieved by the buoy 
and grapple to allow this to be safely done. In this way 
repairs may be made with comparative ease and rapidity. 

The life of a submarine cable under ordinary cir- 
cumstances has not as yet been definitely determined — 
which is the same as saying that it is a long one, since 
numerous cables have been working continuously for 
many years, and there is every reason to believe that 
they will continue doing so for many more to come. 
They must be constantly attended to and repaired, 
however, and the cost of these repairs sometimes 
amounts to fabulous sums. The cable of the Direct 
United States Cable Company, laid in 1874, has cost, 
on an average, $40,000 per annum for the last thirty 
years. 

[44] 



THE SUBMARINE CABLE 

INSTRUMENTAL AIDS 

The instruments used for sending and receiving 
messages over two thousand miles of cable are not the 
comparatively simple transmitters and receivers of land 
telegraphy, where relays can be installed and the current 
increased at various points along the line. The instru- 
ment first used for receiving cable messages was Lord 
Kelvin's "marine galvanometer" referred to a moment 
ago. When this little instrument is suspended near a 
fine-wire coil, it takes a position at right angles to the 
plane of the coil when the current is on, being deflected 
to right or left according to the direction of the current. 
These movements to right or left are interpreted as 
dots and dashes respectively, and thus the Morse code 
can be used as in land telegraphy. 

Another instrument that came into use shortly was 
the "spark recorder" — an instrument so arranged that 
sparks were projected against a surface of paper, or some 
other sensitized surface, passing at uniform speed. The 
message was thus recorded as an undulating line of 
dots or perforations which could be read and transcribed 
into writing by the operator. 

But this instrument was soon replaced by another in- 
strument, the "siphon recorder," first patented by Lord 
Kelvin in 1867. In this, a tube of ink is so arranged 
that as the message comes over the wire fine drops of 
ink are projected upon a piece of paper in a wavy line, 
the dots and dashes of the Morse code being represented 
by deflections of the line of ink-dots to one side or the other 
of a central line on the paper. 

Us] 



SCIENCE IN THE INDUSTRIAL WORLD 

Since this early invention of the siphon recorder many 
improvements have been made in the instrument, several 
of them by Lord Kelvin himself. The principle re- 
mains practically the same, however, and siphon re- 
corders of various kinds are now used almost exclusively 
in submarine telegraphy. 



[461 



Ill 

WIRELESS TELEGRAPHY 

ON Thursday, December 12, 1901, at 12.30 
p.m. Guglielmo Marconi at a station in St. 
Johns, Newfoundland, received a communica- 
tion of the letter S — three dots of the Morse code — sent 
through the air from the wireless telegraphy station at 
Poldhu in England. This was the first wireless commu- 
nication ever sent across the Atlantic Ocean. The news 
of this event created enthusiasm all over the world, and 
excitement in certain commercial centers, but it can 
hardly be said to have created any astonishment: the 
present generation has become too accustomed to mar- 
velous manifestations of electricity. 

The success of Marconi and several other prominent 
scientists in the development of wireless telegraphy is 
the outcome of a long series of experiments dating back 
almost to the beginning of the nineteenth century. 
Most of these early experiments, however, were attempts 
at sending wireless messages through the earth or 
through water rather than through the air, the fact that 
dry air is a poor conductor of electricity for many years 
preventing experiments in telegraphing through this 
medium without some mechanical means of conduction. 
In the middle of the eighteenth century Watson dis- 
covered that water could be made to take the place of 

[47] 



SCIENCE IN THE INDUSTRIAL WORLD 

wires as the return circuit of two batteries. The fact that 
the earth could be made to perform the same function, 
however, was not discovered until many years later. 

In experimenting with land electricity in 1837, 
Steinheil, in England, made the accidental discovery 
that the earth could be made to take the place of the 
return wire of his telegraph. It had occurred to Steinheil 
that the two rails of the railroad track could be utilized 
for sending telegraphic messages in place of two wires. 
He therefore connected the wires from the telegraphic 
instrument with the rails of the track, arranging a 
similar instrument at the station a few miles distant. 
He found, however, that messages could not be trans- 
mitted in this manner, and in investigating to determine 
the cause of this failure, he discovered that the current, 
instead of passing along one rail and returning by the 
other, made a short cut through the earth from rail to 
rail. This suggested the possibility of utilizing the earth 
itself as a conducting medium for wireless telegraphy, 
although experiments in this direction were without 
results for many years. 

WATER AND EARTH AS CONDUCTORS 

About five years later, in 1842, Samuel Morse suc- 
ceeded in sending wireless messages, first across a canal 
and then across a river something like a mile in width. 
He did this by immersing the ends of two telegraph 
wires running parallel along the opposite banks for 
some distance, the four ends of these wires being im- 
mersed at points in the river at which the wires would 

[48] 



WIRELESS TELEGRAPHY 

have crossed the stream had the circuit been contin- 
uous. If one imagines two iron bridges crossing a 
narrow stream at some distance apart, the ends of these 
bridges being connected by two wires running parallel 
on opposite banks, it is obvious that if telegraph in- 
struments are inserted anywhere along these wires, mes- 
sages may be sent and received, a complete circuit being 
formed by the bridges and the wires connecting them. 
If the bridges were removed, however, and the ends 
of the wires at the place of removal immersed in the 
stream by means of metal plates at the points corre- 
sponding to the position of the ends of the bridges, it 
is found that messages may be sent as readily as before 
the bridges were removed, the water or the bed of 
the stream completing the circuit. This is the prin- 
ciple upon which Morse constructed his wireless 
telegraph. But the maximum distance at which he 
was able to convey messages was something like a mile ; 
and in order to do this he found that it was necessary to 
have his wires extended along the banks at least three 
miles. In other words the relative distances at which 
messages could be sent through water was as one to three 
in comparison with the length of the wires on shore. 

No particular advance was made in wireless teleg- 
raphy from this time until about 1880, after the in- 
vention of the telephone. About this time, however, 
Prof. J. Trowbridge, of Harvard, found that if a dynamo 
or coil had two terminals in the earth, an interrupted or 
alternating current passing between them may be de- 
tected by means of a telephone receiver, which is ex- 
tremely sensitive to feeble interrupted currents. Mes- 

VOL. VIII.— 4 [ 49 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

sages in the form of verbal communication could not be 
transmitted in this manner, but if a telegraph instru- 
ment was used the clicking could be readily detected, 
and messages by the Morse code read at a considerable 
distance. Trowbridge suggested that by this means it 
might be possible to establish transatlantic communica- 
tions. He suggested the use of this method, or a modi- 
fication of it, for the communication between vessels at 
sea, and his suggestions were tested practically by 
Graham Bell, of telephone fame. In his experiments 
Bell was able to send and receive messages from ships half 
a mile apart ; but at long distances his attempts were un- 
successful. Messages thus limited were of course of no 
practical importance, and experiments in this direction 
were soon abandoned. 

In 1882, Sir William H. Preece turned to practical 
account the foregoing experiments of Morse and Trow- 
bridge, by sending messages across the Solent to the Isle 
of Wight from the mainland of England. The cable be- 
tween these two places having been damaged and 
rendered useless, Preece erected parallel wires on the 
opposite shores arranged in a manner similar to the 
wires of Morse, but having a telephone receiver inserted, 
which made the detection of feeble currents possible. 
This wireless telegraph worked satisfactorily and was 
used for some time until the cable was repaired. This 
was one of the first successful attempts to turn wireless 
electric telegraphy to practical account. 

Three years later, in 1885, Thomas A. Edison pat- 
ented a system of wireless telegraphy whereby moving 
trains could send and receive messages at any point 

[50] 



WIRELESS TELEGRAPHY 

along the line while going at full speed. This system 
was installed on the Lehigh Valley Railroad in 1887. 
Although the practical working of this telegraph was 
entirely satisfactory, it was not found to pay commer- 
cially, as there was not sufficient demand for such a 
system, and it was shortly abandoned. 

In 1892, Sir William Preece and Mr. A. W. Heaviside, 
experimenting with parallel telegraph lines situated 
some ten miles apart, found that they could send and 
receive messages readily at that distance. Their sys- 
tem was given a practical test shortly after, communica- 
tion by this means being attempted between the coast of 
Wales at Cardiff and two small islands situated about 
three and five miles respectively from the shore. On 
Flat Holm, the nearer of the two islands, messages were 
sent and received successfully from the mainland; but 
on Steep Holm, two miles farther out, the signals could 
be detected, but not distinguished with sufficient clear- 
ness to be read. 

A little later than this Mr. Willoughby S. Smith and 
Mr. W. P. Granville installed a system of communication 
with Fastnet Rock, some seven miles off the coast of 
Ireland, which, although not remarkable for the distance 
to which the messages were sent, was very important 
commercially. Cable communication with this rock, 
on which is located an important lighthouse, was con- 
stantly interfered with by the breaking and wearing out 
of the cable, due to the violence of the waves in that 
vicinity as well as the nature of the ocean bed. To over- 
come this, Smith and Granville cut the cable at some 
distance from shore and grounded the end of it with a 

[51] 



SCIENCE IN THE INDUSTRIAL WORLD 

mushroom anchor at sufficient depth to be beyond the 
destructive action of the waves. Wires were then 
passed over the rock and submerged on both sides and 
a telegraph plant installed, utilizing a modification of 
the system employed by Sir William Preece in his 
experiment. This arrangement solved the question of 
constant communication between the lighthouse and 
the mainland. 



EXPERIMENTS WITH "HERTZIAN WAVES " 

In 1886-7, tne great discovery of Dr. Heinrich Hertz 
that there are waves in the ether apparently identical 
with the light waves but of much lower pitch or period, 
called the attention of the scientific world to the possibil- 
ity of using these vibrations for wireless telegraphy. 
The existence of such "Hertzian waves," electro- 
magnetic in nature, had been suggested several years 
before by Clerk-Maxwell, but his theory had not been 
practically demonstrated until the classic experiments 
of Doctor Hertz. It was found that these waves were 
comparatively tractable and that they could be dealt 
with as if they were light waves — could be reflected, re- 
fracted, and polarized. The possibility of utilizing such 
waves in wireless telegraphy was appreciated at once, 
their action being the basis of all modern wireless tele- 
graphs. 

The obstacle which opposed the use of such electro- 
magnetic waves at a great distance was the difficulty of 
detaching them, rather than that of sending them. But 
in 1 890-1 a "coherer" was invented by Doctor Branly 

[52] 



WIRELESS TELEGRAPHY 

in Paris which was extremely sensitive to these Hert- 
zian waves and by means of which the presence of such 
waves might be detected. Doctor Branly, therefore, 
is usually credited with having developed the little 
instrument that made possible the modern wireless 
telegraph. But it seems that as early as 1880 the dis- 
covery of such a coherer had been made by Prof. D. E. 
Hughes, although this discovery had attracted com- 
paratively little attention. When the discovery of 
Doctor Branly's became known, Sir William Crookes 
at once recalled that he had seen a somewhat similar 
device made ten years before by Professor Hughes. 
Investigation of this showed that Professor Hughes had 
anticipated Doctor Branly's discovery by several years, 
although Dr. Branly's coherer, rather than that of 
Professor Hughes', must be credited with playing the 
important part in the development of wireless telegraphy. 
The principle of this coherer depended upon the 
action of brass filings confined within a vacuum tube, 
these filings being so sensitive to the Hertzian waves 
that the latter may be detected at great distances. Ma- 
king practical application of this discovery, Sir Oliver 
Lodge, in 1893, experimented with a pair of knobs, each 
connected with a Leyden jar placed in the same circuit, 
and a battery and a bell. By this instrument, strokes 
of the bell could be produced by " syntonic" response 
of the electric vibration created by a signal jar some 
distance away. In order to produce this effect the jars 
and their circuit had to be accurately "tuned" — that is, 
have a corresponding number of electric vibrations per 
second. 

[53] 



SCIENCE IN THE INDUSTRIAL WORLD 

This instrument of Sir Oliver Lodge's is probably 
justly considered the ancestor of all the more recent types 
of wireless telegraphs, in which the vibrations, or 
syntonic responses, are similarly dependent upon ac- 
curate tuning. It was by some such apparatus, or 
modification of it, that Prof. A. Popoff, of the Cronstadt 
Torpedo School in Russia, was able, in 1895, to send 
messages successfully to a distance of five kilometers. 

Naturally the scientific world was thrown into a 
state of intense expectation at the possibilities of these 
telegraphs, and various investigators all over the world 
succeeded in producing more or less successful wireless 
telegraphs. Just what position a later generation will 
assign these pioneers in the history of wireless telegraphy 
cannot, of course, be now determined. One fact, how- 
ever, cannot be gainsaid : the man who first succeeded 
in transmitting messages across the ocean was Guglielmo 
Marconi. 

THE WORK OF MARCONI 

Marconi did not discover any new and revolutionary 
principle in his wireless- telegraph system, but rather 
he assembled and improved a vast array of more or 
less scattered facts, unified and adapted them to the 
required end. Morse did the same thing with the land 
telegraph ; yet no one will belittle the part he played in 
introducing the practical telegraph. Possibly future 
generations will regard Marconi as the Morse of wire- 
less telegraphy. 

Between 1894 and 1896 Marconi perfected a most im- 
portant part of his telegraph, the coherer for detecting 

[54] 



WIRELESS TELEGRAPHY 

electric waves. This little instrument is a glass tube less 
than two inches long and of less diameter than the or- 
dinary lead-pencil, having two silver plugs sealed into 
it, each plug with a platinum wire extending from the 
end of the tube. The silver plugs fit tightly into the 
tube, completely rilling it except for a little space be- 
tween their ends in the middle of the tube, this space 
being about one millimeter in length. The little cham- 
ber so formed is filled about half full of nickel and silver 
filings. The air in this space is exhausted and the tube 
permanently sealed. 

Under ordinary circumstances the grains of the nickel 
and silver powder in the little chamber between the ends 
of the plugs lie about "higgledy-piggledy," just as any 
ordinary filings would do under similar circumstances. 
But when the electric waves fall upon them they are 
polarized and assume definite positions, in much the 
same manner as do iron filings on a piece of paper when 
a magnet is passed beneath the sheet. Once the filings 
in Marconi's coherer have been so arranged by the ac- 
tion of the electric waves they tend to remain so, and 
would thus furnish no further means of detecting suc- 
ceeding waves unless they are disarranged in some 
manner; but if the tube is tapped, the grains fall into 
their original position of disarrangement, instantly 
"lining up" as soon as the waves again fall upon them. 

For practical application in wireless telegraphy a 
mechanical device is used which, by a series of extremely 
rapid and gentle tappings, oscillates the little tube in a 
manner barely perceptible to ordinary sight. This 
oscillating tube is connected with a Morse printer, and 

[55] 



SCIENCE IN THE INDUSTRIAL WORLD 

so arranged that a short train of oscillations registers a 
dot, while longer periods of oscillations register dashes. 
If, then, the electric waves are made to fall upon the 
coherer (or receiver, as it may be termed) in longer and 
shorter intervals from the transmitting instrument, a 
series of dots and dashes may be made at will — in short, 
the letters of the Morse code produced. 

Another great improvement in Marconi's wireless 
system was the introduction of his vertical "air- wire" 
or "aerial," which is a vertical wire carried to a great 
height on poles or by means of a kite, such a wire act- 
ing as an electric-wave absorber, collecting the waves 
to act upon the little coherer. A great many of these 
are sometimes used in combination, such "wave-gates" 
being established at various Marconi stations for long- 
distance messages. These aerials are also installed on 
the masts of ships ; in such an arrangement one knob of 
the exciter is attached to a heavy insulated wire which is 
then led up the mast, terminating at the top in a cylinder 
or sheet of zinc, or a piece of wire netting. 

METHODS AND RESULTS 

All these things sound very intricate and complicated 
indeed, and it might be supposed that the actual send- 
ing and receiving of wireless messages by this system is a 
difficult matter. As a matter of fact the operating is 
simplicity itself to the telegraphist. His actions are 
practically the same as if he were sending an ordinary 
land- telegraph message. When he works the key of 
his sending instrument, his dots and dashes set up 

[56] 



WIRELESS TELEGRAPHY 

currents in a large secondary coil which pass as sparks 
across certain " spark-gaps" up along the air- wire of 
the pole to the terminal at the top, whence they are 
scattered broadcast. Some of these are gathered in by 
the wires on the poles at the receiving station, are carried 
down to the detector that sets in motion the Morse in- 
strument, which sounds or prints the message just as in 
the case of the ordinary land telegraph. 

From this it is obvious that the messages thus sent 
are not really transmitted in any aimed direction, but 
are scattered in all directions, and that they would be 
received and recorded at other receiving stations than 
the one intended. To prevent this a system of " tuning " 
has been introduced, so that only instruments tuned 
to a certain number of vibrations per second affect each 
other. Unless the number of vibrations is nearly the 
same, instruments tuned in this manner will not be 
affected by messages from other instruments, and will 
select out only messages intended for themselves and 
sent out by similarly tuned transmitters. If some such 
arrangement as this were not possible, wireless messages 
would be so hopelessly jumbled as to be unintelligible; 
and indeed in practice serious difficulties are sometimes 
encountered where a number of systems are working 
within "striking" distance of each other. 

The progress of wireless telegraphy during the past 
ten years has been so rapid as to seem like a succession 
of triumphs. From the sending of wireless messages a 
few hundred feet by Marconi in London, in 1896, until 
the transmission of complete messages across the 
ocean in 1902, seems but a series of rapid steps, cer- 

[57] 



SCIENCE IN THE INDUSTRIAL WORLD 

tainly unequaled in any previous field of telegraphic 
progress. 

Marconi's first attempts at wireless telegraphy were 
made in his native city of Bologna as early as 1895. 
The following year he went to London and applied for 
patents. Here he submitted his plans to the postal- 
telegraph authorities, having at their head Sir William 
Preece, himself a prominent investigator in wireless 
telegraphy. In order to test the wireless apparatus a 
sending and a receiving station were located on the roof 
of the post-office building and in a small room a hundred 
yards away; and the experiments here conducted were 
followed by other trials at longer distances. 

Early in 1897, Marconi, continuing his experiments 
in England, made attempts at sending messages a 
considerable distance over bodies of water. While 
working at one of these he made the discovery that a 
long air-wire was most essential to successful communi- 
cation, even at comparatively short distances. In this 
experiment he was attempting to send wireless messages 
to an island a little over three miles from the mainland. 
One of the poles for supporting air-wires was ninety 
yards high, but the other one, situated on the cliff of the 
water's edge, was only about thirty yards in height. 
For two days unsuccessful attempts were made with this 
arrangement, and they were watched by several scien- 
tists who were studying the subject on the spot and 
assisting Marconi in his efforts. The attempts were 
about to be abandoned, for the moment at least, as the 
cause of failure could not be determined, when it oc- 
curred to the inventor to lengthen the air-wire by 

[58] 



WIRELESS TELEGRAPHY 

splicing it down to the water's edge, a distance of twenty 
yards more. The result was the immediate response of 
the receiving instrument to the messages sent from the 
other station, every letter being correctly recorded. 

Longer distances were tried at once, and within a 
few months it was possible to send messages across the 
English Channel. Stations were established at points in 
England and France, and communications of all kinds 
passed continually between these points for several 
months. During this time it was ascertained that such 
atmospheric conditions as fog, for example, did not in- 
terfere in any way with the transmission of messages, but 
on the contrary facilitated them. Electrical conditions 
of the atmosphere, however, affected the wireless system 
in much the same manner as they affect the ordinary 
telegraph. 

About this same time an epoch in telegraphy and 
navigation was made by the installation of wireless 
instruments on board one of the Channel boats in the 
North Sea. It was found that the masts of the boat 
afforded excellent means of establishing the air- wire, 
and that communication could be kept up continually 
between the boat and the shore station during the voy- 
age. If anyone had ever doubted the utility of such a 
system, which is hardly likely, these doubts were 
soon dispelled by an incident which occurred soon after 
the establishment of the wireless system on this boat. 
In one of her passages she sighted a small vessel which 
had run ashore in a dangerous position, imperiling the 
lives of the crew. The position of the vessel was 
such that it was impossible to give assistance from 

[59] 



SCIENCE IN THE INDUSTRIAL WORLD 

the Channel boat with safety. Messages were therefore 
sent at once by wireless to the land station, giving the 
position of the stranded boat and asking that assistance 
be sent at once from one of the life-saving stations on 
the coast. The crew was successfully rescued a few 
hours later. 

The wireless system was soon found to be most 
satisfactory in solving the vexatious question of commu- 
nicating with lightships anchored at some distance from 
land. Cable communications with such vessels is out 
of the question because the action of the waves and the 
constant moving about of the vessel wears out a cable 
in a short time. With the wireless system, however, these 
vessels are now kept constantly in communication with 
shore — a most important thing in case of accident to the 
lights, or to the vessels themselves. 

TRANSATLANTIC MESSAGES 

By the autumn of 1901 Marconi had perfected his 
telegraph so that he determined to attempt to send 
messages across the ocean. He therefore sailed to his 
American receiving station in Newfoundland to make 
the attempt. By prearrangement, the station in Poldhu 
was to send messages at stated intervals, and at a cer- 
tain time during each day after Marconi's arrival. The 
message agreed upon was to be three dots, indicating the 
letter S of the Morse code. This was to be repeated a 
certain number of times at intervals of three minutes 
between the hours of three o'clock and six o'clock 
p.m., English time, which would be from about 11.30 
a.m., to 2.30 p.m., Newfoundland time. On Dec. 12th, 

[60] 




MECHANISMS INVOLVED IN WIRELESS TELEGRAPHY. 

The lower figure shows a dynamo used in generating a current for transatlantic 
messages. The middle figure shows the approved method of construction of towers 
to carry the wires at a receiving station. The upper figure reproduces a photograph 
taken at night at a wireless station. The electrical display so vividly recorded on the 
photographic plate was altogether invisible to the eye. 



WIRELESS TELEGRAPHY 

about noon, these messages were received repeatedly 
and unmistakably at the St. Johns' station, and they 
were again heard at intervals on the following day. 
The miraculous had been accomplished; a message 
had crossed the Atlantic and been recorded without 
the aid of any mechanical conductor except that 
furnished by nature. 

In the meanwhile, however, other inventors besides 
Marconi, in almost every other country, had been ex- 
perimenting, and naval and merchant vessels were being 
equipped with wireless apparatus. Wireless messages to 
and from vessels two days after leaving their docks, to 
and from friends on shore, became a fad on transatlantic 
liners ; and passing vessels fifty or one hundred miles 
apart communicated important news to each other or 
" talked" together for hours as they passed. As the 
sailing points of most vessels are not from the extreme 
points of land, and as wireless stations are located in 
such positions, it was possible to send communications 
from ship to shore several days after the boat had sailed. 
A steamship sailing from Antwerp, for example, which 
passed around the southern coast of England without 
touching, might be able to keep up her communication 
with shore fully three days after sailing; and Marconi 
soon improved his instruments so that at a much longer 
distance messages might be received on shipboard, even 
when the vessel was unable to send back replies. 

TUNING THE MESSAGES 

In March of 1902, Marconi, on the steamship 
Philadelphia, was able to receive messages at a dis- 

[61] 



SCIENCE IN THE INDUSTRIAL WORLD 

tance of almost 1550 miles from the sending point, these 
messages being actually in words and not mere prede- 
termined signals. Mere signaling could be determined at 
a distance something over two thousand miles. On this 
eventful voyage the fact was established by Marconi 
that such messages could only be received by a vessel, 
or vessels, tuned to the same electrical pitch as the shore 
instrument, and that no insurmountable interference 
would be offered by messages of a different pitch 
passing through the atmosphere at the same time. This 
was established by the fact that several other vessels 
equipped with Marconi instruments, but keyed to a 
different electrical pitch, had been on the ocean at the 
same time, and had been sending messages continually 
during the passage. The Umbria, for example, had been 
nearer the sending station, and in the same receiving 
zone as the Philadelphia, and yet she had neither re- 
ceived these messages nor had her own messages been 
interfered with by them. 

This seemed to establish Marconi's contention, which 
had heretofore been greatly doubted, that different sets 
of instruments might be worked within short distances of 
each other — within distances of five inches, the inventor 
said — without interfering with each other; and his 
messages were assured against possible " tapping of the 
circuit," by the two hundred and fifty different "tun- 
ings" that he was able to give his instrument. "It 
seems to be a matter of popular belief," wrote Marconi, 
"that any receiver within effective range of the transmit- 
ter is capable of tapping each message sent, or in other 
words, that there can be no secrecy of communica- 

[6a] 



WIRELESS TELEGRAPHY 

tion by my system. Were this so, a very important 
limitation would be imposed upon the practical useful- 
ness of the system ; but by the introduction of improve- 
ments and radical modifications in the system, and by a 
systematical application of the principles of electrical 
resonance, this objection has, in a very great measure, 
been overcome." 

THE PRACTICAL STATUS OF WIRELESS TELEGRAPHY 

On December 21, 1902, three entire messages, of con- 
siderable length, were sent between Poldhu and the 
Table Head station on Cape Breton Island, these being 
the first complete messages ever sent across the Atlantic. 
Four weeks later congratulatory messages between King 
Edward VII and President Roosevelt were exchanged, 
establishing officially the possibility of practical wireless 
telegraphy at long distances. 

Some of the conclusions reached by Marconi in his 
extensive experiments are both interesting and in- 
structive. He finds that wireless telegraphy is much 
more effective over marine areas than over ordinary land 
surfaces, the relative distance to which such messages 
may be sent being in the proportion of about two to one. 
He finds, furthermore, that atmospheric conditions, such 
as ordinary rain- or snow-storms, high winds, etc., do 
not seriously affect the wireless signals, although, of 
course, electrical storms are disastrous to them. Air- 
wires fixed upon poles about two hundred feet in 
height give the most uniformly satisfactory results ; but 
strangely enough there is no advantage in placing the 

[63] 



SCIENCE IN THE INDUSTRIAL WORLD 

pole on a high hill for marine signaling. He has found 
also that certain geological formations are more re- 
sponsive than others, although this phenomenon can- 
not be explained, as the action of the earth in connection 
with a wireless system is not as yet understood. 

The present state of wireless telegraphy may be 
summed up in the statement that it is entirely practical 
commercially, even between points separated by an 
ocean. Continents, lightships, war vessels on long cruises, 
and islands situated in tempestuous waters, have all 
been brought into continuous communication with 
shore points, and at a much less expenditure of money 
than is possible with submarine cables. 

The history of the wireless telegraphy up to the 
present day is comparable with the history of submarine 
cables between 1858 and 1866. The cable of '58 carried 
a few messages and then ceased to work. Other shorter 
cables were laid, studied and improved upon, and 
by 1866 the first really successful transatlantic cable was 
laid and operated. Similarly in 1902 wireless messages 
were sent across the Atlantic — messages of sufficient 
length to prove the possibility of accomplishing such a 
thing — and finally regular communication on a paying 
commercial basis for transatlantic messages has been 
established. No one now seriously doubts that the 
millions of dollars' worth of submarine cables now at 
the bottom of the ocean is doomed to go the way of the 
stage-coach and pony express. They have served their 
purpose and, fortunately, have "paid their way" well; 
but that they are obsolescent few thinking people will 
pretend to doubt. 

[64] 



WIRELESS TELEGRAPHY 

At the present time at least a dozen systems of wire- 
less telegraphy are in use, in various parts of the world. 
These all resemble one another closely, although each 
has some features specifically different from any other. 
Thus the DeForest system, the invention of the Amer- 
ican, Lee DeForest, which made such a good record in 
the Far East during the Russo-Japanese war in the 
service of the London Times, employs alternating- 
current generators as a prime source of electric oscilla- 
tions. In this the filings-coherer is not used, but in place 
of it a "responder" which utilizes a telephone at the 
receiving end. 

Among the other well-known systems in general use 
are the Lodge- Muirhead system, employed in Great 
Britain; the Slaby-Arco system, the Braun-Siemens- 
Halske system, in Germany ; the Branley-Popp system, 
used extensively in France, the Rochefort system, used 
in the French navy, the Ducretet-PopofT system of Rus- 
sia, the Fessenden system, and numerous systems 
operated by ambitious amateurs, which sometimes inter- 
fere with the workings of the regular commercial lines. 

Four different wireless systems are in use by various 
departments of the United States government. The 
navy uses the Slaby-Arco system ; the army, the Braun 
system; the Army Signal Corps, the Wildman system; 
and the Weather Bureau, the Fessenden system. 

VOL. VIII. — 5 



[6S] 



IV 

THE DEVELOPMENT OF THE TELEPHONE 

FULLY to understand the action of the telephone 
it should be recalled that all sounds are produced 
by vibrations of matter, and that any sound to be 
appreciated by the sense of hearing must be conveyed 
to the sense organs of the ear by the repetition of sound 
vibrations through some such medium as air, water, iron, 
etc., air of course being the usual medium. Any body 
from which sound proceeds, therefore, is in a state of 
vibration. This may be demonstrated by the simple 
experiment of striking a thin glass jar, causing it to 
vibrate and produce sound, the vibratory motion being 
distinctly felt if the jar is touched lightly when the sound 
is loudest, and gradually ceasing as the sound dimin- 
ishes. The same vibrations and sounds may be pro- 
duced by drawing a violin bow across the top of the 
jar; and if little balls of wood are suspended by several 
inches of string so that they just touch the sides of the 
jar near the top, these will be thrown into a state of 
vibration, oscillating back and forth against the jar as 
the violin bow is drawn across it. In this way the 
sound vibrations are made evident to sight as well as 
hearing. 

In this experiment the air acts as the vibrating me- 
dium for conveying the sound waves from the glass jar 

[66] 



DEVELOPMENT OF THE TELEPHONE 

to the ear; for if the jar were not surrounded by some 
medium capable of transmitting similar vibrations, no 
sound could be heard. If, for example, the jar were in a 
vacuum, the sound of its vibration would not be con- 
veyed to the ear. This was demonstrated by the strik- 
ing experiment made by Francis Hauksbee in 1705. 

In this experiment Hauksbee placed a bell rung by 
clockwork in the receiver of an air-pump. So long as the 
air was not exhausted from the receiver the ringing of 
the bell was heard distinctly, but as the air became ex- 
hausted the sound of the ringing gradually diminished 
until it entirely disappeared when the vacuum had been 
produced, although the vibrations of the striker could 
still be seen. In this condition the sound could be again 
distinctly heard by allowing a little air to enter the 
receiver, or by bringing a wire into contact with the bell, 
the sound waves being conveyed along the wire to the 
air outside, which then acted as a medium for their 
transmission. 

The appreciation of sounds by the sense of hearing 
is a function of the brain, and like all such functions 
can only be vaguely understood. The mechanical ar- 
rangement of the ear for receiving impressions of the 
sound waves, however, is comparatively simple, being 
the same as the mechanical apparatus made artificially 
to interpret sound vibration. A thin membrane, like 
a miniature drum-head, receives these vibrations just as 
in the case of the membrane or diaphragm used in the 
telephone receiver, and transfers them to the proper 
"center" in the brain, where they are interpreted by 
the sense of hearing. That this drum-head or diaphragm 

[67] 



SCIENCE IN THE INDUSTRIAL WORLD 

arrangement of the ear acts in accordance with mechan- 
ical laws was strikingly shown by an experiment of Bell 
with his telephone, in which part of one of his earlier 
instruments was actually made of the human ear. 

AN EARLY CONCEPTION OF THE TELEPHONE 

The possibility of sending verbal messages at long 
distances through some other medium besides that of the 
atmosphere was conceived at least two centuries before 
the accomplishment of the practical telephone in 1876. 
In 1667 the English scientist, Robert Hooke, wrote of a 
method of communication by telephone as follows; 

"It is now possible to hear a whisper at a furlong's 
distance, it having been already done; and perhaps 
the nature of the thing would not make it more possible, 
though that furlong should be ten times multiplied. And 
though some famous authors have affirmed it impos- 
sible to hear through the thinnest plate of Muscovy 
glass, yet I know a way by which it is easy enough to 
hear one speak through a wall a yard thick. 

"It has not yet been thoroughly examined how far 
otacousticons may be improved, nor what other ways 
there may be of quickening our hearing, or conveying 
sound through other bodies than the air; for that is not 
the only medium I can assure the reader that I have, by 
the help of a distended wire, propagated the sound to a 
very considerable distance in an instant, or with as 
seemingly quick a motion as that of light, at least incom- 
parably quicker than that which at the same time was 
propagated through the air; and this not only in a 

[68] 



DEVELOPMENT OF THE TELEPHONE 

straight line or direct, but in one bended in many 
angles." 

Just what Hooke's method of telephoning may have 
been does not appear. Presumably it was some such 
arrangement as the string-diaphragm " speaking tele- 
phone" to be referred to in a moment. But in any 
event nothing of practical importance ever came 
of it. 

A step toward the development of a practical tele- 
phone was taken in 1 819 by Sir Charles Wheatstone who 
invented what is known as the " magic lyre telephone," 
by which musical notes were made to respond to similar 
tones at some distances. But it was not until several 
years after the invention of the telegraph that any serious 
attempts were made to perfect the speaking telephone. 
About 1867, however, a great number of instruments 
known as "membrane telephones" were put upon the 
market as toys. This form of telephone, familiar to every 
schoolboy in his studies of physics, consists of two 
cups, the bottoms of which are made of a tightly 
stretched membrane, or parchment, perforated in the 
middle by a string fastened with a knot at the end, and 
connecting the two cups. With such an arrangement a 
person speaking into one of these cups as into the 
transmitter of a telephone may convey messages a con- 
siderable distance to a person holding the other cup 
to the ear, the string meanwhile being drawn taut. 
Verbal messages have been sent and received in this way 
at distances ranging from 1 50 to 1 70 yards, but these could 
only be sent when the string was continuous and not 
resting against any intervening object. They could not, 

[69] 



SCIENCE IN THE INDUSTRIAL WORLD 

in other words, be sent around a corner. In 1876, 
however, Bregnet improved this simple telephone so 
that it was possible to send a message over a string 
which made several turns or angles. To do this he in- 
serted little drum-like structures at the turning points of 
the string, these little drums being made of cylinders 
with the ends covered by membranes through the cen- 
tre of which the string passed, thus reproducing the 
vibrations set up by the voice in the transmitter and 
passing them along the line to the receiver. 

Such telephones, however, were at best only toys 
for communicating verbal messages a few yards. But 
at about this time the possibility of utilizing electricity 
and magnetism for conveying these vibrations to a great 
distance seems to have occurred to a number of investi- 
gators. It had been discovered in 1837 by Page in 
America that a magnetic bar would emit sounds when 
rapidly magnetized and demagnetized; and in i860 Reis 
had invented a "musical telephone." This instrument 
was composed of two distinct parts, a sounder and a 
receiver. The sounder consisted of a sounding-box 
having across its opening a membrane, in the centre of 
which there was fitted a small disk of platinum, having 
above this a metallic point. At one side of the box 
there was a tube corresponding to a speaking-tube, ar- 
ranged so as to receive the sound and direct it toward 
the membrane through the interior of the box. 

The receiving instrument consisted of a small iron 
rod about the size of a knitting-needle placed upon a 
sounding-box. About this rod was wound an insulated 
electrified wire, the whole apparatus having the appear- 

[70] 



DEVELOPMENT OF THE TELEPHONE 

ance of a long bobbin or a spool of wire fastened upon 
an ordinary box. 

If a musician, stationed before the opening of the tube 
of the receiving-box, played upon such an instrument 
as the violin or cornet, the sounds were recorded by 
the vibrations on the membrane and platinum disk, 
by means of the point, causing a series of breaks in the 
current which could be conveyed by wire to the rod and 
bobbin of the receiver at a considerable distance. By 
this arrangement various airs and melodies might be 
heard and distinguished, although it was impossible 
to distinguish different qualities of tone. That is, while 
the melody itself could be readily distinguished it was 
impossible to tell whether the instrument playing was a 
violin, flute, or cornet. This instrument was not, 
therefore, a speaking telephone, but simply a "musical 
telephone," as it was called. 

BOURSEUL SUGGESTS AN ELECTRICAL TELEPHONE 

In 1854 Mr. Charles Bourseul made the definite sug- 
gestion of the possibility of speech being transmitted by 
electrical means. At that time, although Bourseul's 
statement was made with scientific knowledge of the 
subject and by logical deduction based on that knowl- 
edge, scientists were not inclined to agree with him as to 
the possibility of this suggestion in actual practice. This 
communication, however, had the effect of calling at- 
tention to the subject, and paving the way for the in- 
vention of the speaking telephone. In his paper Bour- 
seul said, in part: — 

[71] 



SCIENCE IN THE INDUSTRIAL WORLD 

" After the telegraphic marvels which can repro- 
duce at a distance handwritings, or even more or less 
complicated drawings, it may appear impossible to 
penetrate further into the regions of the marvelous. Yet 
we will try to advance a few steps further. I have, for 
example, asked myself whether speech itself may not 
be transmitted by electricity — in a word, if what is 
spoken in Vienna may not be heard in Paris. The thing 
is practicable in this way: — 

"We know that sounds are made by vibrations, and 
adapted to the ear by the same vibrations which are 
reproduced by the intervening medium. But the in- 
tensity of the vibrations diminishes very rapidly with 
the distance ; so that it is, even with the aid of speaking- 
tubes and trumpets, impossible to exceed somewhat 
narrow limits. Suppose that a man speaks near a 
movable disk, sufficiently flexible to lose none of the 
vibrations of the voice, and that this disk alternately 
makes and breaks the currents from a battery: you may 
have at a distance another disk, which will simultane- 
ously execute the same vibrations. 

"it is true that the intensity of the sounds produced by 
means of the voice at the point of departure where the 
first disk vibrates will be variable and will be constant 
at the point of arrival, where the other disk vibrates by 
means of electricity; but it has been shown that this 
does not change the sounds. It is, moreover, evident 
that the sounds will be reproduced at the same pitch. " 

Here was the correct conception, theoretically, at 
least, of a practical telephone. But Bourseul did not 

[72] 



DEVELOPMENT OF THE TELEPHONE 

take the necessary steps and construct a practical in- 
strument along the lines outlined in his paper, and the 
matter dropped out of sight for a decade. 

AN INTERESTING COINCIDENCE 

Meanwhile the Americans had been making ex- 
periments, and on February 14, 1876, Prof. Alexander 
Graham Bell, of Boston, and two hours later, on the 
same day, Elisha Gray, of Chicago, each filed in the 
patent offices at Washington, a caveat, or provisional 
specification, of a practical electric telephone. At the 
Centennial Exposition in Philadelphia in that year, 
Gray exhibited a multiplex telegraph, and Bell exhibited 
his " wonder of wonders," as Lord Kelvin termed that 
telephone, in addressing the British Association at 
Glasgow a few weeks later. 

"In the department of telegraphs in the United States 
section," said Lord Kelvin (then Professor Thomson), 
"I saw and heard Mr. Elisha Gray's electric telegraph 
of wonderful construction, which can repeat four dis- 
patches at the same time in the Morse code, and, 
with some improvements in detail, this instrument is 
evidently capable of a fourfold delivery. In the Cana- 
dian department I heard, ' To be or not to be ? There's 
the rub,' uttered through a telegraphic wire, and its 
pronunciation by electricity only made the rallying tone 
of the monosyllables more emphatic. The wires also 
repeated some extracts from the New York papers. With 
my own ears I heard all this, distinctly articulated 
through the slender circular disk formed by the arma- 

[73] 



SCIENCE IN THE INDUSTRIAL WORLD 

ture of an electromagnet. It was my fellow juryman, 
Professor Watson, who, at the other extremity of the 
line, uttered these words in a loud and distinct voice, 
while applying his mouth to a tightly stretched mem- 
brane provided with a small piece of soft iron, which 
executed movements corresponding to the sound vibra- 
tions of the air close to an electric magnet introduced 
into the circuit. This discovery, the wonder of wonders 
in electric telegraphy, is due to a young fellow country- 
man of our own, Mr. Graham Bell, a native of Edin- 
burgh, and now naturalized in New York. 

"It is impossible not to admire the daring invention 
by which we have been able to realize with these simple 
expedients the complex problem of reproducing by 
electricity the tone and delicate articulations of voice 
and speech; and it was necessary, in order to obtain 
this result, to find out the means of varying the intensity 
of the current in the same proportion as the inflections 
of the sound emitted by the voice." 

DR. GRAHAM BELL DESCRIBES HIS INVENTION 

A year later Bell himself described his invention, 
and the interesting experiments leading up to it, in a 
paper read before The Society of Telegraph Engineers. 

"I hit upon an expedient for determining the pitch 
which at that time I thought to be original with my- 
self," he said. "It consisted in vibrating a tuning-fork 
in front of the mouth while the position of the vocal 
organs for the various vowel sounds were silently taken. 
It was found that each vowel position caused the rein- 
forcement of some particular fork or forks. 

[74] 





bfl 


* ^^^fcHk -r~ 








^ 


i 


A >^(L^ 


Sf 


-■..•»« 







DR. GRAHAM BELL IN NEW YORK COMMUNICATING FOR THE FIRST TIME WITH 
CHICAGO BY TELEPHONE. 



DEVELOPMENT OF THE TELEPHONE 

"I wrote an account of these researches to Mr. 
Alexander J. Ellis, of London. In reply he informed 
me that the experiments related had already been per- 
formed by Helmholtz, and in a much more perfect 
manner than I had done. Indeed, he said that Helm- 
holtz had not only analyzed the vowel sounds into their 
constituent musical elements but had actually per- 
formed the synthesis of them. 

"He had succeeded in producing, artificially, certain 
of the vowel sounds by causing tuning-forks of different 
pitch to vibrate simultaneously by means of an electric 
current. Mr. Ellis was kind enough to grant me an 
interview for the purpose of explaining the apparatus 
employed by Helmholtz in producing these extraordi- 
nary effects, and I spent the greater part of a delightful 
day with him in investigating the subject. At that time, 
however, I was too slightly acquainted with the laws 
of electricity fully to understand the explanations given ; 
but the interview had the effect of arousing my interest 
in the subject of sound and electricity, and I did not 
rest until I had obtained possession of a copy of Helm- 
holtz' s great work, and had attempted, in a crude and 
imperfect manner, it is true, to reproduce the results. 
While reflecting upon the possibilities of the produc- 
tion of sound by electrical means, it struck me that the 
principle of vibrating a tuning-fork by the intermittent 
attraction of an electromagnet might be applied to 
the electrical production of music. 

"I imagined to myself a series of tuning-forks of dif- 
ferent pitches, arranged to vibrate automatically in the 
manner shown by Helmholtz, each fork interrupting 

[75] 



SCIENCE IN THE INDUSTRIAL WORLD 

at every vibration a voltaic current; and the thought 
occurred, ' Why should not the depression of a key like 
that of a piano direct the interrupted current from 
any one of these forks, through a telegraph wire, to a 
series of electromagnets operating the strings of a piano 
or other musical instrument, in which case a person 
might play the tuning-fork piano in one place and the 
music be audible from the electromagnet in a distant 
city?' 

"The more I reflected upon this arrangement the 
more feasible did it seem to me ; indeed, I saw no reason 
why the depression of a number of keys at the tuning- 
fork end of the circuit should not be followed by the 
audible production of a full chord from the piano in a 
distant city, each tuning-fork affecting at the receiving 
end that string of the piano with which it was in unison. 
At this time the interest which I felt in electricity led 
me to study the various systems of telegraphy in use in 
this country and in America. I was struck with the 
simplicity of the Morse alphabet, and with the fact that 
it could be read by sound. Instead of having the dots 
and dashes recorded upon paper, the operators were in 
the habit of observing the duration of the click in the 
instruments, and in this way were enabled to distin- 
guish by ear the various signals. 

"It struck me that in a similar manner the duration 
of a musical note might be made to represent the dot or 
dash of the telegraph code, so that a person might oper- 
ate one of the keys of the tuning-fork piano referred to 
above, and the duration of the sound proceeding from 
the corresponding string of the distant piano be ob- 

[76] 



DEVELOPMENT OF THE TELEPHONE 

served by an operator standing there. It seemed to me 
that in this way a number of distinct telegraph messages 
might be sent simultaneously from the tuning-fork piano 
to the other end of the circuit, by operators, each ma- 
nipulating a different key of the instrument. These 
messages would be read by operators stationed at the 
distant piano, each receiving operator listening for 
signals of a certain definite pitch, and ignoring all others. 
In this way could be accomplished the simultaneous 
transmission of a number of telegraphic messages 
along a simple wire, the number being limited only 
by the delicacy of the listener's ear. The idea of in- 
creasing the carrying power of a telegraph wire in this 
way took complete possession of my mind, and it was 
this practical end that I had in view when I commenced 
my researches in electric telephony." 

Bell then entered into a brief discussion of telephonic 
currents, with graphic illustrations, and continued : — 

"Nine varieties of telephonic currents may be distin- 
guished, but it will only be necessary to show you six 
of these. The primary varieties designated are ' inter- 
mittent/ 'pulsatory,' and 'undulatory.' 

" Sub- varieties of these can be distinguished as ' direct ' 
or ' reversed' currents according as the electrical im- 
pulses are all of one kind or are alternately positive and 
negative. 'Direct' currents may still further be dis- 
tinguished as 'positive' or 'negative,' according as the 
impulses are of one kind or of the other. 

"An intermittent current is characterized by the al- 
ternate presence and absence of electricity upon the 
circuit; 

[77] 



SCIENCE IN THE INDUSTRIAL WORLD 

"A pulsatory current results from sudden or instan- 
taneous changes in the intensity of a continuous current ; 
and 

"An undulatory current is a current of electricity, the 
intensity of which varies in a manner proportional to 
the velocity of the motion of a particle of air during the 
production of a sound; thus, the curve representing 
graphically the undulatory current for a simple musical 
tone is the curve expressive of a simple pendulous vi- 
bration — that is, a sinusoidal curve 

"I have before alluded to the invention by my father 
of a system of physiological symbols for representing 
the action of the vocal organs, and I had been invited 
by the Boston Board of Education to conduct a series 
of experiments with the system in the Boston school 
for the deaf and dumb. It is well known that deaf- 
mutes are dumb because they are deaf, and that there 
is no defect in their vocal organs to incapacitate them 
from utterance. Hence it was thought that my father's 
system of pictorial symbols, popularly known as visible 
speech, might prove a means whereby we could teach the 
deaf and dumb to use their vocal organs and to speak. 
The great success of these experiments urged upon me 
the advisability of devising methods of exhibiting the 
vibrations of sound optically, for use in teaching the 
deaf and dumb. For some time I carried on experi- 
ments with the manometric capsule of Koenig, and 
with the phonautograph of Leon Scott. The scientific 
apparatus in the Institute of Technology in Boston was 
freely placed at my disposal for these experiments, and 
it happened at that time a student of the Institute of 

[78] 



DEVELOPMENT OF THE TELEPHONE 

Technology, Mr. Maurey, had invented an improve- 
ment upon the phonautograph. He had succeeded in 
vibrating by the voice a stylus of wood about a foot in 
length which was attached to the membrane of the 
phonautograph, and in this way he had been enabled 
to obtain large tracings upon a plane surface of smoked 
glass. With this apparatus I succeeded in producing 
very beautiful tracings of the vibrations of the air for 
vowel sounds. I was much struck with this improved 
form of apparatus, and it occurred to me that there was 
a remarkable likeness between the manner in which 
the piece of wood was vibrated by the membrane of the 
phonautograph and the manner in which the ossiculcB 
of the human ear were moved by the tympanic mem- 
brane. I determined, therefore, to construct a phon- 
autograph modeled still more closely upon the mechan- 
ism of the human ear, and for this purpose I sought the 
assistance of a distinguished aurist in Boston, Dr. 
Clarence J. Blake. He suggested the use of the human 
ear itself as a phonautograph, instead of making an 
artificial imitation of it. The idea was novel and struck 
me accordingly, and I requested my friend to prepare a 
specimen for me, which he did. The stapes was re- 
moved and a stylus of hay about an inch in length 
was attached to the end of the incus. Upon moistening 
the membrana tympani and the ossiculce with a mixture 
of glycerin and water, the necessary mobility of the parts 
was obtained; and upon singing into the external arti- 
ficial ear the stylus of hay was thrown into vibration, 
and tracings were obtained upon a plane surface of 
smoked glass passed rapidly underneath. 

[79] 



SCIENCE IN THE INDUSTRIAL WORLD 

"While engaged in these experiments I was struck 
with the remarkable disproportion in weight between 
the membrane and the boneils that were vibrated by it. 
It occurred to me that if a membrane as thin as tissue- 
paper could control the vibration of bones that were, 
compared to it, of immense size and weight, why should 
not a larger and thicker membrane be able to vibrate a 
piece of iron in front of an electromagnet, in which 
case the complication of steel rods, shown in my first 
form of telephone, could be done away with, and a 
simple piece of iron attached to a membrane be placed 
at either end of the telegraphic circuit. 

"The results, however, were unsatisfactory and dis- 
couraging. My friend, Mr. Thomas A. Watson, who 
assisted me in the first experiment, declared that he 
heard a faint sound proceed from the telephone at his 
end of the circuit, but I was unable to verify his asser- 
tion. After many experiments attended by the same 
only partially successful results, I determined to reduce 
the size and weight of the spring as much as possible. 
For this purpose I glued a piece of clock-spring, about 
the size and shape of my thumb-nail, firmly to the centre 
of the diaphragm, and had a similar instrument at the 
other end; we were then enabled to obtain distinctly 
audible effects. 

" I remember an experiment made with this telephone, 
which at the time gave me great satisfaction and de- 
light. One of the telephones was placed in my lecture 
room at the Boston University, and the other in the 
basement of the adjoining building. One of my 
students repaired to the distant telephone to observe the 

[so] 



DEVELOPMENT OF THE TELEPHONE 

effects of articulate speech, while I uttered the sentence, 
'Do you understand what I say?' into the telephone 
placed in the lecture hall. To my delight an answer 
was returned through the instrument itself, articulate 
sounds proceeded from the steel spring attached to the 
membrane, and I heard the sentence, 'Yes, I under- 
stand you perfectly.' It is a mistake, however, to sup- 
pose that the articulation was by any means perfect, 
and expectancy no doubt had a great deal to do with 
my recognition of the sentence; still, the articulation 
was there, and I recognized the fact that the indistinct- 
ness was entirely due to the imperfection of the instru- 
ment. I will not trouble you by detailing the various 
stages through which the apparatus passed, but shall 
merely say that after a time I produced a form of in- 
strument, which served very well as a receiving telephone. 
In this condition my invention was exhibited at the Cen- 
tennial Exhibition in Philadelphia." 

BELL VERSUS GRAY 

Reference is made in this quotation from Professor 
Bell's paper to " intermittent," "pulsatory," and 
"undulatory" currents and the difference in the nature 
of these currents, and an appreciation of these differ- 
ences is very important in understanding the working 
of the speaking telephone. It was an important feature 
of the controversy between Bell and Gray in settling the 
question of priority in the invention of the telephone. 
As explained by Bell, intermittent currents are those 
interrupted to produce sounds quite instantaneous; 

VOL. VIII. — 6 f 81 1 



SCIENCE IN THE INDUSTRIAL WORLD 

pulsatory currents produce only sounds differing in 
intensity; while undulatory currents are those which 
alternately diminish and increase. These last are the 
currents essential to the modern telephone, and it was 
largely upon his knowledge of the nature and action of 
such currents that Bell based his contention of priority 
over Gray in his intimate knowledge of the actual work- 
ings of the telephone. 

It will be recalled that the caveat sent to the patent 
office by Bell reached there only two hours before a 
similar caveat sent by Elisha Gray. The patent 
office, therefore, issued the patent to Bell, although 
the time between the receipt of the two caveats was so 
short that common justice would demand that both 
Bell and Gray be considered as equally entitled to the 
credit of inventing the telephone, provided both in- 
struments described were equally practical. Of course 
in the mere issuance of the patent, Bell was as legally 
entitled to his claim as if the difference in time of 
making the application had been days or weeks instead 
of hours; but Bell contended, probably with good 
ground for his contention, that Gray did not at the 
time understand the importance of what are known 
as the undulatory currents. He did refer to them 
specifically in his caveat, to be sure, but Bell pointed out 
that the currents thus referred to were really the pul- 
satory currents and not the true undulatory ones. 
This, however, is the theoretical and not the practical 
side of the question. The demonstration that a speak- 
ing telephone was a practical possibility was made 
by Bell and not by Gray, and he must, therefore, go 

[82] 



DEVELOPMENT OF THE TELEPHONE 

down in history as the inventor of the first practical 
instrument of this kind. 



PRACTICAL IMPROVEMENTS 

After Bell's invention became known a host of similar 
inventions were made. None of these differed in prin- 
ciple, however, from the original telephone invented 
by Bell. A great number of improvements were made 
both in the transmitter and receiver of the instrument, 
but these were purely improvements upon the mechani- 
cal application of the principles involved, and not depar- 
tures from the principle itself. 

A great improvement upon the type of receiver was 
made by Thomas A. Edison; and in 1877 Emil Ber- 
liner invented what is known as a microphone trans- 
mitter — an apparatus which converts feeble sounds 
into much louder sounds. By the addition of these two 
inventions the telephone was greatly improved, and 
sending and receiving messages at long distance became 
possible. 

Berliner's microphone transmitter consists of a dia- 
phragm with a metal patch in the centre. Against this 
a metal knob is pressed lightly by an adjusting-screw, 
the result of this arrangement being an apparatus which 
greatly magnified the sound effects. 

Three months after Berliner produced his microphone 
transmitter, another instrument designed for a similar 
purpose was invented by Edison. This consists of a dia- 
phragm having a platinum patch in the centre for an 
electrode. Against this a hard point, made of plumbago 

[83] 



SCIENCE IN THE INDUSTRIAL WORLD 

and vulcanized rubber, is pressed by means of a long 
spring, the amount of pressure being adjusted by a 
screw near the base. This transmitter worked admir- 
ably, and, as improved by the inventor shortly after, con- 
stituted an excellent and practical instrument. Other 
transmitters were invented by Professor Hughes and 
Francis Blake, the Hughes transmitter being the 
popular one in Europe, while the Blake transmitter 
came generally into use in America. 

Within the last few years what is known as the long- 
distance telephone, connecting points at a distance of 
a thousand miles or more, has been perfected. This 
does not differ in principle, of course, from the ordi- 
nary telephone, the difference being represented largely 
by the material used in the conducting wires. For 
short distances the ordinary iron wire answers all 
practical requirements; but this material is a rela- 
tively poor conducting medium, and copper, being a 
much better conductor, is necessary for long-distance 
telephones. 

In addition to this improvement in the conducting 
medium it has been found necessary to increase the sen- 
sitiveness of the transmitter in long-distance telephones. 
For, unlike the telegraph, no practical system of relays 
for strengthening the current has been perfected as yet, 
although the limit of long-distance telephony is greatly 
increased by inserting self-induction coils at intervals 
along the line. 

The first long-distance transmitter was what is 
known as the Hunnings' transmitter. This consists 
of a shallow vertical box with insulated sides, and 

[8 4 ] 



DEVELOPMENT OF THE TELEPHONE 

a metallic back and front. The front of the box is 
made of very thin metal and acts as a diaphragm, the 
interior of the box being filled loosely with hard carbon 
granules. The current from the battery passes from 
the diaphragm through the carbon granules to the back 
of the chamber, the vibrations of the diaphragm caus- 
ing vigorous vibrations of the granules, thus producing 
long sounds. A modification and improvement of this 
chamber has been made by A. C. White in America, 
and this is the transmitter, known as the " solid back" 
transmitter, now in general use on long-distance tele- 
phones in the United States. 

TELEPHONE EQUIPMENT 

The question of equipment and operation of telephones 
over any amount of territory large or small, is one 
that is constantly occupying the attention of engineers, 
as the almost universal use of this instrument renders 
even the slightest improvement in the facility and di- 
rectness of communication a matter of the greatest 
importance to both the public and the telephone 
companies. 

"Three distinct types of telephone equipment have 
been developed," explains a recent writer in the Elec- 
trical Review, "the magneto or local-battery, the 
common-battery or lamp-signal, and the automatic 
system. The first two may be further subdivided into 
the transfer and the multiple systems. . . . 

"The trunking or transfer system is a development 
of the original transfer system. It is due to an effort 

[8 5 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

to meet the increasing demands of the rapidly growing 
telephone systems. In the early days of telephones, 
when there were but few subscribers, but more than 
one operator could take care of, the calls were trans- 
ferred from one operator to another by what was 
known as a transfer. Later, the multiple switchboard 
was devised, thus eliminating the transfer. Now the 
still greater increase in number of telephones has car- 
ried the capacity beyond that of the multiple switch- 
board, thus making necessary the establishment of 
branch exchanges with trunk connections." 

The growth of the telephone has been such that in 
the larger cities a great many exchanges have been 
found necessary. In the five boroughs of New York 
city, for example, there are at the present moment 
(19 10) fifty-seven exchanges in operation, and new ones 
are constantly being established. It is obvious, there- 
fore, that under these conditions, the multiple switch- 
board is no longer the most economical form of 
equipment, since the large majority of a subscriber's 
calls will probably be for a station other than his 
own. 

Hence in large cities it has become the practice to 
do away with the subscriber's multiple switchboard 
at his own exchange, and treat every call as a " trunked " 
call. This method has proved expensive both in first 
cost and operation, and out of it a system, technically 
known as the " semi-automatic, " has been developed, 
which eliminates a considerable number of the operators 
necessary in the manual system, and does not require 
the intricate mechanism of the automatic. It can be 

[86] 



DEVELOPMENT OF THE TELEPHONE 

installed wherever the lamp-signal equipment is em- 
ployed. Briefly, it may be described as follows: 

"A subscriber, upon lifting his receiver from the 
hook, operates in the main office a line-relay similar 
to that used in the modern lamp-signal board, but this, 
instead of lighting a line-lamp, energizes a simple 
selector-switch which selects an operator who is not 
busy and, in turn, selects a connecting cord which is 
not busy, and lights the lamp associated with this 
cord. The current lighting this lamp passes through 
a low-wound relay, which connects the operator with 
the subscriber. Upon receiving the number of the 
instrument wanted, the operator inserts the plug in 
the multiple, and rings. Upon inserting the plug in 
the jack, the cord-lamp is automatically extinguished 
and the operator's listening-set is disconnected at the 
same time, leaving the two subscribers to converse 
in privacy.' ' 

Automatic telephone systems, which dispense with 
manually operated central exchanges, are installed 
and working satisfactorily in many places throughout 
the United States at the present time. They are par- 
ticularly popular in the Middle West, Chicago having 
such a system with over ten thousand subscribers. 
The system works perfectly for short-distance messages 
— such, for example, as in the urban service or be- 
tween a large city and its suburbs — but it is not adapted 
to long-distance communications. 

The telephone instrument itself resembles the or- 
dinary wall-piece, with bells, receivers, and trans- 
mitters, but in addition has what is known as a 

[87] 



SCIENCE IN THE INDUSTRIAL WORLD 

"calling-dial." This is a circular metal piece, near 
the edge of which are ten finger-holes, numbered 
from o to 9. When a subscriber wishes to call up any- 
one he removes the receiver, and turns the dial so that 
the finger-holes corresponding to the digits of the num- 
ber he is seeking are brought in succession to a certain 
point on the rim of the dial. For example, if he wishes 
to call 973 he first turns the "9" finger-hole to the stop 
on the indicator and allows it to return to its normal 
position, doing the same thing successively with the 
figures 7 and 3. He then pushes a button, which rings 
the bell of the person wanted. If the 'phone he wishes 
to call is busy at the time a peculiar buzzing sound 
notifies him that such is the case. 



THE WIRELESS TELEPHONE 

The advantages of a system of telegraphy that does 
away with wires are too obvious for discussion, yet any 
system of communication whereby messages must be 
spelled out slowly by means of dots and dashes is mani- 
festly inferior to a system of enunciated words, such as 
telephonic communications. 

When Marconi and his associates in experimental 
wireless telegraphy set at rest forever all doubts as to 
the possibility of electric communication through the 
air by means of the Hertzian waves, they removed at 
the same time all doubt as to the possibility of eventually 
accomplishing spoken communications through space 
in a similar manner. In theory, at least, it should be 
possible to send wireless telephonic messages as well as 

[88] 




MESSAGES BY WIRELESS TELEGRAPH AND WIRELESS TELEPHONE. 

The upper figure shows an operator receiving a wireless message from across 
the ocean. It will be seen that he actually receives the message with the aid of a 
telephone. The lower figure represents trie simple apparatus used in sending and 
receiving messages by the wireless telephone. "Wireless" is in a sense a mis- 
nomer in each case, since wires are necessarily used at sending and receiving stations. 
Once under way, however, the messages are transmitted through the ether, inde- 
pendently of any material substance. 



DEVELOPMENT OF THE TELEPHONE 

telegraphic ones. But it took many years of study 
and experiment before the marvel was actually accom- 
plished. In round numbers the practical wireless tele- 
graph preceded the wireless telephone by a decade. 

In point of practical accomplishment, American in- 
ventors have shown the way in the development of 
wireless telephony, as they did half a century earlier in 
telegraphy. And as the name of Morse must always 
be associated with telegraphy, so the name of Dr. Lee 
DeForest, a native of Western America, will always be 
linked with practical wireless telephony. In 1907, 
Doctor DeForest built his first instruments and trans- 
mitted the music of a phonograph a few blocks to a 
receiving station in New York. A few weeks later he 
was able to report by voice the results of yacht races 
a distance of about four miles. In the autumn of the 
same year his instruments were installed on the ships 
of the American fleet of war- vessels on their trip around 
the globe, and kept those vessels in verbal communica- 
tion with each other, in storm and calm, during the en- 
tire voyage. A year later messages had been sent and 
received a distance of over five hundred miles, and a 
practical working-service between Chicago and Mil- 
waukee put into operation. 

Theoretically there is very little difference between 
the wireless telephone and the one requiring connect- 
ing wires. The vibrations of the voice, in each instance, 
affect a disk which releases electrical impulses of vary- 
ing degree. In one case the speaker transmits his voice 
along a wire, in the other through the air, just as he 
might shout to a friend a block away, with this im- 

[89] 



SCIENCE IN THE INDUSTRIAL WORLD 

portant difference, that by means of the radiophone 
the sound of his voice may be hurled miles instead of 
feet. 

The sending instrument first used by Doctor De 
Forest, and which may be taken as the model for suc- 
ceeding instruments, consists of an ordinary micro- 
phone transmitter, in which the various vibrations 
caused by the voice affect the intensity of an electric 
current. The ether is made to receive a continuous 
chain of impulses caused by a rapidly vibrating arc 
light — DudelPs arc, as it is called. The oscillations of 
this arc light are modified in accordance with the varia- 
tions of the voice as it causes fluctuations of the micro- 
phone current. These impulses affect the circuit of the 
receiving apparatus, modify it, and the current so 
modified passes through the filament of an incandescent 
lamp, causing the light to vary in accordance with the 
original vibrations. The variation of the light causes 
constant changes in the conducting power of the air 
remaining in the bulb. This rarefied gap in the lamp 
is used in place of a wire for completing the circuit of a 
telephone receiver, the varying current causing the re- 
ceiver to emit sound waves just as the wire telephone 
does. 

In some of the more recent instruments there is an 
oscillating arrangement by means of which electrical 
impulses are constantly sent out at a tremendous rate 
of repetition. This causes a faint humming in the re- 
ceivers, altogether too slight to be annoying to the lis- 
tener. The vibrations of the voice cause lapses or breaks 
in the oscillating impulses, this arrangement increasing 

[90] 



DEVELOPMENT OF THE TELEPHONE 

the efficiency of the instrument over those in which the 
vibrations of the voice-impulses are sent forth. The 
scientific explanation of why such an arrangement is 
more efficient, is so complicated as to mean little to 
the average layman. A recent writer explains it by 
metaphor as follows: — 

"Imagine a man standing on the bank of a small 
pond, throwing bricks into the water. These create 
big waves at broken intervals which can be managed 
to convey signals of a code. That is the old spark of 
telegraphy. 

"Now, instead of a man with bricks, picture a huge 
funnel containing sand, which allows one grain at a 
time to fall to the water at a high rate of speed. The 
waves sent forth are barely perceptible, but are none 
the less existent. Each time the man wants to send a 
signal or impulse he shuts off the flow of sand. He can 
do this with infinitely greater speed than the man can 
throw bricks. Hence it follows that the number of 
waves or impulses transmitted in a given time is only 
limited by the grains of sand that can be dropped. Re- 
sults are convincing. Under the old system about forty 
words a minute could be transmitted. Under the new, 
40,000 words an hour are possible, could they be sent 
so rapidly." 1 

The infinite advantage of wireless over wire tele- 
phones has been demonstrated recently on many oc- 
casions. Storms and accidents of all kinds are forever 
putting connecting wires out of commission, completely 
isolating whole regions for hours or even days at a time. 
Even submarine cables have the advantage over ordi- 

[91] 



SCIENCE IN THE INDUSTRIAL WORLD 

nary terrestrial wires in this respect. A few years ago a 
Boston correspondent of a New York paper, who was 
reporting a murder trial of considerable notoriety, 
found that a severe snow-storm had destroyed all tele- 
graphic and telephonic communication with the metrop- 
olis, thus blocking him and his brother reporters in 
their daily stories. In this extremity a brilliant idea oc- 
curred to him. The cables to Europe were working as 
usual. By sending his story to New York by cable via 
London this keen-witted correspondent accomplished 
a " scoop" that is now newspaper-reporter history. 
To-day he would have done the same thing via wireless 
telephone or telegraph. But it would have been no 
" scoop." For every other reporter would have done the 
same thing, many of them as an ordinary routine. 

One advantage of the wireless telephone over the 
wireless telegraph is the fact of its compactness. A good 
working instrument can be made small enough to be 
carried in a coat pocket. In this day of air-ships, where 
every superfluous ounce of weight is dispensed with, 
the compactness of the wireless telephone makes it 
doubly valuable. It adds practically nothing to the 
weight of the car, and yet it affords a means of con- 
stant communication between the air-ship and distant 
points. It is declared by many serious thinkers that 
the development of the wireless telephone plays a 
most important part in the development and practical 
usefulness of the air-ship. But this is only one of a 
thousand important applications of wireless telegraphy. 



[92] 



THE EDISON PHONOGRAPH 

IF a popular vote were to be taken to decide what 
invention was considered the most wonderful of 
all those produced during the latter part of the 
nineteenth century, it is probable that the majority of 
votes would be cast in favor of the phonograph. The 
X-ray apparatus for photographing through opaque 
substances, and the telephone, would surely come in 
for a large vote. But to most persons, nothing quite 
so much approaches the realm of the miraculous as the 
little instrument, small enough to be carried in a 
good-sized coat pocket, which reproduces accurately 
all manner of sounds from violin notes to steam sirens. 

It seems superfluous to say that the inventor of this 
marvelous instrument is Thomas A. Edison. The 
name " Edison phonograph" has become generic as 
well as descriptive. 

On the 31st of July, 1877, Edison first applied for a 
patent on his " speaking phonograph." It was by no 
means the first instrument ever made upon which words 
could be recorded. Even as early as 1856, Mr. Leo Scott 
produced what was known as a " phonautograph " — 
an instrument so arranged that the vibrations made by 
sounds were recorded on smoked glass, or some other 
similar substance, by means of a needle attached 

[93] 



SCIENCE IN THE INDUSTRIAL WORLD 

to a diaphragm. This instrument worked perfectly in 
simply recording sounds; but it did not reproduce these 
sounds, and apparently the inventor made no attempts 
to do so. His claim to priority in inventing a speak- 
ing phonograph, therefore, is absolutely groundless. 
A more reasonable claim might have been made by the 
Frenchman, M. Charles Cros, who, in April, 1877, sent 
to the Academy of Science, in Paris, a paper describing 
the way in which an instrument might be made that 
would reproduce such sounds as the human voice. But 
this was simply a description of a possible instrument, 
the actual construction of which had not been attempted. 
And when Abbe Leblanc, a short time later, constructed 
an instrument after the method described by Cros, it 
failed utterly as a sound-producer. It is evident, 
therefore, that Edison's claim to the invention of the 
first phonograph stands absolutely unchallenged. 

In contrast to the wonderful effects that may be 
produced by this instrument is the simplicity of the con- 
struction of the instrument itself. The Edison phono- 
graph of 1877 was fitted with a cylinder covered with tin- 
foil for receiving the impression of the sound waves. 
This cylinder was so arranged that, as it revolved, it 
moved at a definite rate of speed from right to left, this 
movement being controlled by the action of screw 
threads. Above this cylinder, and arranged so that a 
needle point pressed into the tin-foil, was the recorder. 
This consisted of a cylinder about two inches in diam- 
eter, over the lower end of which was stretched a dia- 
phragm of parchment or gold-beater's skin, with a needle 
or recording point fastened to the centre. When sounds 

[94] 



THE EDISON PHONOGRAPH 

were projected into the upper end of the cylinder the 
vibrations thus set up caused the diaphragm to vibrate 
back and forth. This vibration, producing upward and 
downward movements of the needle, caused it to make 
indentations on the rotating cylinder of tin-foil be- 
neath, recording precisely the vibrations made by 
the sounds in the cylinder. These sounds could then 
be reproduced by setting back the cylinder and rotating 
it at the same rate of speed as before, causing the 
needle to pass over the indentations in the grooves made 
while recording, thus reproducing the vibrations of the 
diaphragm. This was the principle of Edison's first 
phonograph, and this is the underlying principle of his 
own later perfected instruments as well as of all other 
forms of "talking machines," although the details of 
the operating mechanism have been greatly modified. 

Between 1877 and 1888 Edison was constantly ma- 
king improvements in his invention until he had per- 
fected the phonograph practically as we know it to-day. 
In the newer instruments the parchment diaphragm 
of the older instrument has been replaced by a thin 
glass plate; and the cylinders are no longer made of 
tin-foil but of a dark-brown waxy substance familiar 
as phonograph " records." Clockwork or electricity 
has been applied for rotating the cylinder, so that the 
old winding movement of the crank is now done 
mechanically. 

A great improvement has been made in the pointed 
marker or recorder, and the corresponding instrument 
for reproducing the records. In place of the steel 
needle used on the first instruments, the marker is now 

[95] 



SCIENCE IN THE INDUSTRIAL WORLD 

made of a small piece of sapphire with a chisel-shaped 
edge, while the point used in reproducing the sounds is 
also made of sapphire with its edges rounded and of a 
peculiar shape. The shape of this little point is very 
important, as clear reproductions are largely dependent 
upon its construction. 

The advantage of the wax cylinders over those made 
of tin-foil is that they are more permanent and may be 
duplicated by molding an indefinite number of times. 
Furthermore they record sounds readily and reproduce 
them better. 

For reproducing sounds three things are necessary 
in the shape and arrangement of the indentations in the 
grooves made by the recorder. It will be recalled that 
the pitch of any sound depends upon its number of 
vibrations per second — sounds of a high pitch or fre- 
quency having more vibrations than those of a low 
pitch. On the cylinder, therefore, a high note is recorded 
by a certain number of indentations in a given space, 
while low notes have a correspondingly less number. 
The number of indentations is quite independent of 
the loudness of the sound to be reproduced ; this is con- 
trolled by the depth of the indentations made, a loud 
sound producing deep indentations while softer sounds 
are represented by shallow ones. 

The fact that these little indentations will reproduce 
sounds seems wonderful enough to the ordinary mind, 
but the real wonder lies in the fact that qualities of 
sounds are also reproduced in the little grooves — the 
violin, for example, being almost as easily distinguish- 
able from the French horn as it is in the orchestra itself. 

[96] 



THE EDISON PHONOGRAPH 

This quality of sound is reproduced by the form of the 
indentations in the wax, regardless of their frequency or 
depth. When it is considered that all the complicated 
vibrations determining pitch, loudness, and quality 
of sounds, are recorded by minute, almost microscopic, 
indentations in little grooves scarcely perceptible to 
the naked eye, it is little wonder that the Edison pho- 
nograph remains a constant source of marvel. 

In the issue of the North American Review for May- 
June, 1878, Edison described his then recent invention, 
and recorded some of the prophecies as to the possibili- 
ties of its use in the future. He said in part : — 

"The apparatus now being perfected in mechanical 
details will be the standard phonograph, and may be 
used for all purposes except such as require special form 
of matrix, such as toys, clocks, etc., for an indefinite 
repetition of the same thing. The main utility of the 
phonograph being, however, for the purposes of letter- 
writing and other forms of dictation, the design is 
made with a view of its utility for that purpose. 

"The general principles of construction are a flat 
plate or disk, with a spiral groove on the face, worked by 
clockwork underneath the plate; the grooves are cut 
very closely together, so as to give a great total length to 
each length of surface — a close calculation gives as 
the capacity of each sheet of foil nearly 40,000 words. 
The sheets being but ten inches square, the cost is so 
trifling that but a hundred words might be put on a 
single sheet economically. 

"The practical application of this form of phono- 
graph is very simple. A sheet of foil is placed in the 

VOL. VIII.— 7 [ 97 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

phonograph, the clockwork set in motion, and the 
matter dictated into the mouthpiece without other 
effort than when dictating to a stenographer. It is then 
removed, placed in a suitable form of envelope, and sent 
through the ordinary channels of correspondence to 
whom it is designed. He, placing it upon his phono- 
graph, starts his clockwork, and listens to what his cor- 
respondent has to say." 

It will be seen that even at this time Edison foresaw 
clearly the future that was in store for his invention. 
And the significant part of his statement, foreshadow- 
ing the use of phonographs in dictating letters and 
documents, is now put in practical e very-day use by 
thousands of persons all over the world. The cylinder 
records, however, are not used as Edison suggested — 
that is, sent through the mails in special cases or en- 
velopes — but are turned over to typists who record the 
dictation on typewriting machines in the ordinary 
manner. This is but one of the many ways in which 
the phonograph has proved itself a most useful inven- 
tion. But even without this important commercial 
value, the instrument affords a means of harmless amuse- 
ment and entertainment of no small significance in 
the healthful development of a community. 



[98] 



VI 

PRIMITIVE BOOKS 

IN considering the work of ancient scribes, one is met 
at the outset with the curious fact that it is some- 
what difficult to say just what constitutes a book. 
We may assume, however, for the present purpose, that 
a book is any written or printed document, more exten- 
sive than a mere letter, intended to convey information 
from one person to another. Our first concern will be 
with the primitive types of books. Making a very bold 
and general classification, there may be said to be five 
of these, namely, first, the papyrus roll, as used by 
the early Egyptians; second, the tablet of baked clay; 
third, the prism or cylinder of the same material, used 
by the Babylonians and Assyrians; fourth, the palm- 
leaf type, as employed by the Hindus and their followers 
of the Far East ; fifth, folded books. 

It is perhaps impossible to say with certainty which 
of these types is the most primitive. The oldest books 
in existence are, doubtless, those of the Babylonians; 
but the great permanency of these is explained by the 
material of which they are composed, and it does not 
follow that they were necessarily the first books to be 
made. We know that the Egyptians employed a papyrus 
roll from the earliest historical periods, and that the 
Hindus made their palm-leaf books at a very early 

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SCIENCE IN THE INDUSTRIAL WORLD 

day. In short, every civilized nation is discovered, at 
the very dawn of its history, in full possession of a system 
of book-making; each nation having, seemingly, acted 
under the stress of necessity in selecting a material made 
accessible by its surroundings. 

It is equally impossible to decide the question as to 
whether one nation borrowed from another in develop- 
ing the idea of book-making. The diversity of material 
does not suggest such borrowing, and it would seem that 
such widely separated nations as, for example, the 
Aztecs of Mexico, the Egyptians, and the Hindus, could 
not greatly have influenced one another, unless, indeed, 
the origin of books dates back to a period when all of 
these nations were still members of the same prehis- 
toric body politic, — a supposition which is not altogether 
gratuitous, but which carries us too far into the realm 
of conjecture to be pursued further here. 

Limiting our view strictly to the historic period, we 
find, as has been said, the five types of books in general 
use. We have now to consider briefly the distinguishing 
characteristics of each of these types, before going on to 
note the steps of development through which the modern 
book was evolved. First let us give attention to the 
papyrus roll of the Egyptians. As has been said, this 
type of book was employed in Egypt from the earliest 
day of the historical period. As is well known, papyrus 
is a species of primitive paper — the word paper being, 
indeed, a derivative of papyrus — which was made of 
stalks of the papyrus plant placed together to form two 
thin layers, the fibers of one crossing those of the other, 
and the whole made into a thin, firm sheet with the aid 

[ioo] 



PRIMITIVE BOOKS 

of glue and mechanical pressure. The strips of papyrus 
were usually from eight to fourteen inches in width, and 
from a few feet to several yards in length. This scroll 
was not used, as might perhaps have been expected, 
for the insertion of a single continuous column of 
writing. A moment's consideration will make it clear 
that such a method would have created difficulties both 
for the scribe and for the reader; therefore the much 
more convenient method was adopted of writing lines 
a few inches in length, so placed as to form transverse 
columns, which followed one another in regular sequence 
from the beginning to the end of the scroll. Each 
column was therefore closely similar, in size and ap- 
pearance, to the page of a modern book. It will be seen 
that such a scroll could be read conveniently by rolling 
up one end as fast as the other was unrolled, the process, 
however, requiring the use of both hands. When not 
in use, the book formed a compact roll convenient either 
for carrying about or for storing on a shelf. 

That this form of book had great practical merits is 
shown by the fact that it was adopted by the Greeks and 
Romans. Parchment was the substitute for papyrus 
as material for the roll, but the form of the book itself 
was not changed, in any essential, throughout the clas- 
sical period. All of the Greek and Roman books con- 
sisted of such rolls, and this, presumably, was the form 
also in which the Hebrew writings were first given to 
the world. It will be recalled that the classical writers 
usually divided their works into so-called books of com- 
paratively small extent. Thus the History of Herodo- 
tus, as everyone knows, is divided into eight books. 

[101] 



SCIENCE IN THE INDUSTRIAL WORLD 

It is probable that, originally, each book occupied a 
single papyrus, or parchment, roll, and that the division 
into books was originally suggested for mechanical 
convenience to avoid too large a roll. A single work — 
what we should call a single volume — thus consisted, 
ordinarily, of several parchment, or papyrus, rolls. 

TEKRA-COTTA BOOKS OF THE BABYLONIANS AND 
ASSYRIANS 

Since the papyrus roll was so convenient and so ex- 
tensively used, there can be little doubt that it made 
its way, at one time or another, to Mesopotamia, the 
home of the Babylonians and Assyrians, who were so 
long the greatest rivals of the Egyptians. This sup- 
position is more than an inference, for the sculptures of 
the Assyrians show their scribes making records upon 
what appear to be scrolls of some flexible material. It 
seems tolerably certain that no traces of books of this 
character have been preserved in Mesopotamia, the 
explanation being that the climatic conditions are very 
different there from those existing in Egypt. Even 
had the Babylonians used papyrus habitually, it is 
highly improbable that a single scrap of this material 
would have been preserved to the present time. The 
fact that no books of the classical period have been pre- 
served in Greece or in Italy, with the single exception 
of a library in the buried city of Herculaneum, gives 
full explanation of the absence of papyrus books from 
the Babylonian tumuli. 

But, on the other hand, it is highly probable that the 
[102] 



PRIMITIVE BOOKS 

Babylonians and Assyrians were never altogether con- 
verted to the use of the Eygptian form of book, and that, 
from first to last, they used of a preference the one 
which is so characteristic of their civilization, and of 
which tens of thousands of specimens have been pre- 
served; namely, the tablet, or cylinder, of baked clay. 
These tablet books first came to the eye of modern 
scholarship through the excavations that were made at 
the site of old Nineveh by the Frenchman Botta, and a 
little later by Sir Henry Layard, about the middle of 
the nineteenth century. The most important collection 
that early investigations of Layard brought to light was 
found in the ruins of the library of the famous Assyrian 
king, Assurbanipal. This collection had peculiar in- 
terest because it contained, among other things, the 
fragments of the sacred books of the Babylonians and 
Assyrians, including creation and deluge stories some- 
what closely akin to those of the Hebrews. Subsequent 
explorations revealed vast quantities of similar books 
in the ruins of much older cities than Nineveh, in 
particular at Nippur, one of the oldest cities of Baby- 
lonia, where the famous researches of the University of 
Pennsylvania have been carried out, and where many 
thousands of tablets in a single collection have been 
discovered. 

All these tablets are by no means entitled to be called 
books, many of them being mere business documents, 
such as bills of sale, records of loans, and the like. 
But others of the tablets preserve the text of literary 
documents precisely comparable to modern books. 
The tablets are usually oblong in shape. The usual 

[103] 



SCIENCE IN THE INDUSTRIAL WORLD 

size is perhaps three or four inches in width by five or 
six in length and half an inch to an inch in thickness. 
Each tablet is complete in itself, constituting virtually 
the leaves of a book, but there are no means of holding 
these leaves together. They were merely piled one 
upon another on the shelves of the library. As an aid 
to the reader, an expedient was adopted which the 
printers of modern books invented, independently, 
some thousands of years later, and which has only 
recently gone out of vogue; the expedient, namely, of 
repeating at the foot of each page the first word of the 
next. 

The writing upon the clay tablet was done with a 
sharp curved implement, which readily made the little 
arrow-shaped stroke which is the foundation of the 
Babylonian script. The deftness and regularity with 
which these so-called cuneiform inscriptions were made, 
has been the amazement of all modern scholars who 
have studied them. Notwithstanding the relative per- 
fection of execution, however, these inscriptions are 
extremely difficult to decipher. This is particularly 
true of some of the smaller tablets where the character 
is very small. It will be understood, of course, that the 
inscriptions were made on these tablets while the clay, 
of which they were composed, was in a soft condition. 
The tablet was subsequently either dried in the sun, or 
baked in an oven, becoming a brick of almost imperish- 
able hardness. This, of course, accounts for the preser- 
vation of the vast quantities of Babylonian and As- 
syrian records. Thanks to the imperishable material 
of these books, the present-day student of ancient his- 

[104] 



PRIMITIVE BOOKS 

tory is gaining a more direct and specific knowledge 
of oriental history than we shall, perhaps, ever be able 
to obtain regarding much more recent classical periods. 
For, as already pointed out, the Greeks and Romans 
made their records chiefly on perishable materials. 

In addition to the flat tablet, the Babylonians and 
Assyrians wrote some of their books on large prisms 
and cylinders. Some of these cylinders are as much 
as two feet in length, and eight to ten inches in diameter. 
Being made of the same material as the tablets, they are 
necessarily heavy and cumbersome, yet they were in 
some ways more convenient for reading, since they were 
perforated longitudinally, and placed on a spindle, 
so as to revolve. In some cases the writing runs from 
end to end of the cylinder, which is then suspended 
horizontally. In other cases the cylinder is upright, 
the columns running from top to bottom. In the latter 
case, the book is usually not a true cylinder, but a 
prism of six, eight, or ten sides, each side holding a 
separate column of writing like the page of a book. 
These prisms and cylinders were commonly selected 
by the kings to contain records of their deeds. Thus 
the British Museum contains prisms on which are 
recorded achievements of such famous conquerors as 
Sargon, Sennecharib and the Elamite warrior, Cyrus. 
The last-named cylinder has peculiar interest because it 
describes the taking of Babylon. There is also a 
cylinder of King Nabonidus, the ruler of Babylon, 
which contains another account of the same trans- 
action. It appears that Nabonidus capitulated to Cyrus, 
and that there was no such scene of carnage as the 

[105] 



SCIENCE IN THE INDUSTRIAL WORLD 

Hebrew imagination has pictured in connection with 
the fall of the famous city. Neither was there a King 
Belshazzar in Babylon at this, or at any other time. 
King Nabonidus, however, had a son named Belshazzar 
who probably served in the army and whom the Hebrews 
probably confused with his father, as they also con- 
fused the capture of Babylon by Cyrus with its subse- 
quent capture by Darius. The oriental mind was, and 
is, curiously defective in its conceptions of the neces- 
sities of exact history. 

THE PALM-LEAF BOOKS OF THE HINDUS 

The examples of the Egyptians and Babylonians il- 
lustrate the fact that the material selected for book- 
making depends upon natural conditions of the environ- 
ment. So when we go still farther to the East, it is not 
surprising that we find the knowledge of the Hindus 
recorded on books of a quite novel character. The 
type here is a peculiar form of palm leaf, two or three 
inches in width, cut in sections of a convenient length, 
say from one to two feet. Such strips of palm leaf 
afford a convenient surface for receiving the writing, 
and they have the merit of requiring no preliminary 
treatment beyond mere drying. Each strip is comparable 
to the leaf of a book, the writing, as usual, being placed 
upon it longitudinally. The leaves are then piled 
upon one another in sequence. Sometimes they were 
perforated at each end and strung together like Vene- 
tian blinds. 

This principle of long, relatively narrow leaves, in- 
[106] 



PRIMITIVE BOOKS 

scribed on only one side and piled together to make a 
book, was adopted everywhere in the Far East. The 
palm leaf was the model, as just suggested, and it con- 
tinued a favorite medium; but, in course of time, various 
nations, perhaps rinding it difficult to secure the native 
material, imitated it with various artificial mediums. 
Thus the sacred books of the Buddhists in India itself 
and in Burma are sometimes written on strips of gold, 
wood, or of ivory, and the books of Tibet, though re- 
taining the essential character of the palm-leaf book, 
are inscribed on what is virtually a form of paper. 
Even cloth was sometimes made to serve the same 
purpose. 

It will be obvious that this palm-leaf type of book has 
many elements of convenience. It is light and portable, 
unlike the Babylonian book which it resembled in ap- 
pearance, and it is certainly more easy to manage in 
reading than the papyrus roll of the Egyptians. To 
handle the palm leaves is virtually equivalent to turning 
the leaves of a modern book, and it seems odd that 
some inventive Hindu did not hit upon the idea of 
fastening the leaves together at one end, leaving the 
other free. Had this been done, the type of the modern 
European book would have been invented. 

FOLDED BOOKS 

A much nearer approach to the form of the modern 
book was made by an obscure nation called the Battaks, 
who inhabited the Island of Sumatra. This people 
invented, or adopted from some unknown source, a 

[107] 



SCIENCE IN THE INDUSTRIAL WORLD 

form of book consisting of a long strip of thin bark, five 
or six inches in width, and therefore closely resembling 
a strip of Egyptian papyrus. The writing of the Battak 
— usually ornamented with pictorial designs — was 
placed in transverse columns on this strip, precisely 
after the Egyptian manner. But they make a funda- 
mental innovation in the art of book-making, for the 
Battak, instead of rolling his strip of bark in the simple 
Egyptian manner, folded it into accordion-like pleats; 
so that it took precisely the form of a modern book 
with leaves uncut at the edge, each column of writing 
forming a single page. Wooden covers were then put 
on either side of the book, the whole being sometimes 
bound together with a piece of snakeskin. Had the 
Battak scribe gone one step further by cutting the leaves 
of his book and writing on both sides, we should have 
had the exact prototype of the modern European book. 
But, notwithstanding the obvious economy of material 
that this expedient would have brought about, there is 
no evidence that any Battak scribe ever utilized this idea. 
So the Battak book, though standing one step nearer 
to the modern form, is still imperfect. 

Curiously enough, the Aztec Indians of Mexico were 
found in possession of books precisely of the Battak type 
when the Europeans first invaded their territory. The 
material of these Aztec books was a kind of paper, so 
the Americans had, in this regard, advanced upon the 
Battaks; but the leaves of these books, like the others, 
remained uncut so that half the writing surface was still 
wasted. 

We have now to inquire how, and when, the final 
[108] 



PRIMITIVE BOOKS 

step in the mechanical art of book-making was 
taken. 

Notwithstanding the wide diversity of materials of the 
various books that we have examined, it appears there 
is one interesting peculiarity in which they all agree; 
without exception they are written upon one side of the 
leaf whether that leaf be a papyrus roll, a slab of clay, 
or a palm leaf with its various artificial modifications. 
The cylinder of the Babylonian might, indeed, be named 
as an exception, since here the entire available surface 
is utilized. But as this unique form of book had no 
successor, it may be disregarded for the present purpose. 
As to all the others, it is obvious that half the available 
writing surface of the material used is wasted. The ex- 
travagance of this method must have been obvious to 
the ancient scribes, particularly when it chanced that 
papyrus and parchment were difficult to secure. The 
fact that the backs of papyrus rolls were often used to 
receive odd bits of writing, such as memoranda, personal 
accounts, and the like, is in itself proof that the matter 
received attention, but it is equally clear that the manner 
of rolling a book left the outer surface too much exposed 
to make its regular use feasible. Nor did the Egyptian 
ever change his method in this regard. Perhaps the 
abundance of papyrus plants, and the relative ease of 
securing book material, withheld the stimulus that might 
otherwise have led to invention. But, outside of Egypt, 
this stimulus made itself felt with sufficient vigor. In 
the time of the Seleucids, the inheritors of Alexander's 
empire in western Asia found it very difficult to secure 
papyrus, and were forced to the use of parchment which 

[109] 



SCIENCE IN THE INDUSTRIAL WORLD 

was said to have been invented at Pergamus, but which 
was probably only perfected there, since a statement of 
Herodotus makes it clear that the use of skins in writing 
had been practised long before. In any event, parch- 
ment eventually superseded papyrus as a book material 
everywhere in the Western world, outside of Egypt. It 
continued to be almost the exclusive book material every- 
where in Europe until paper was invented, late in the 
Middle Ages. 

It must be obvious that parchment, being made of spe- 
cially prepared skins of animals, is a much more costly 
material than papyrus. In point of fact, it became very 
costly indeed in the Middle Ages, and, in securing it, 
the scribes of the time were often put to their wits' end. 
Here, then, was the traditional stimulus to invention — 
necessity. The unmarked outer surface of this parch- 
ment roll must have persistently appealed to the eye 
of even the least inventive scribe, and we can little doubt 
that many a writer was led to utilize this surface, even 
while the form of the book still remained a roll. It must 
be added, however, that this is an inference only, for 
no rolls written on both sides have been preserved to 
us: a fact sufficiently explained by the almost total 
loss of the earliest examples of European book-making. 
The oldest parchment books that are preserved date 
only from the third or fourth century, a. d., at which 
time the folded book, with writing on both sides of the 
leaf precisely as in the modern printed book, had made 
its appearance. 

By what steps had this transition from the roll to the 
folded book been accomplished ? We can only guess. 

[no] 



PRIMITIVE BOOKS 

A natural inference, based on the observation of the 
Battak and Aztec books, would be that some one was 
led to adopt the same plan of folding the parchment 
scroll, which we have seen in vogue amongst these 
nations, and that the constant wearing away of the edge 
of such a book, with the consequent exposure of the un- 
used surface, forced new possibilities upon the attention. 
But it is always futile, in such a case as this, to attempt 
to reason from effects back to causes. Things seem so 
easy after they are done, that it is more natural to 
accuse our predecessors of stupidity for their delay 
rather than to give them credit for their invention. 
And in this particular case, it seems so natural a thing 
to use both sides of a sheet of paper in writing, that 
one can hardly avoid wondering at the conservatism 
of the many generations of the scribes of antiquity who 
wasted half their writing material. 

But whatever the exact stages of transition, the folded 
book with cut leaves, inscribed upon both surfaces, the 
said leaves fastened together at one edge and bound into 
a volume almost precisely like a modern book, had 
fully established itself in popular usage by the third or 
fourth century of our era. Since that time there have 
been numerous minor modifications or shifts of fashion 
in book-making, but the essential principles of the mere 
mechanics of the art have not been modified. When, 
in the fifteenth century, the printing-press began to 
supersede the old-time scribe, there was no question 
of inventing a new type of book; the whole thought of 
the makers of printing-presses was merely how to adapt 
their machinery to the form of book which custom had 

Em] 



SCIENCE IN THE INDUSTRIAL WORLD 

sanctioned for many centuries ; which, as we know, it 
still sanctions. If this form of book lacks anything of 
perfection, no one has, as yet, pointed out a plan for 
its betterment. 



THE TEXT OF ANCIENT BOOKS 

Thus far we have considered the book as a mechanical 
contrivance for the reception of writing. We have now 
to turn attention to that really essential feature, the 
writing itself. Here, again, it is the mechanics of the 
subject that will generally claim our attention. That is 
to say, we shall disregard questions of philology and of 
systems of writing, and call attention merely to certain 
peculiarities that were common to all the different sys- 
tems, and the fact that these may be considered as char- 
acterizing certain peculiarities of the mental develop- 
ment of our race. Our inquiry will have to do with such 
practicalities of writing as the direction of the script, 
questions of the division of words, the punctuation of 
sentences, capitalization, and paragraphing. All of 
which convenient accessories seem fundamentally es- 
sential to us, but none of which was utilized by the earli- 
est makers of books. 

An examination of any ordinary scroll of Egyptian 
writing will show that the figures of birds, animals, and 
men all face in one direction. In some scrolls they are 
all turned to the right, and in others all to the left, and, 
as a rule, the same plan holds throughout any single 
piece of writing. The explanation of this is that the 
Egyptian writing is always to be read from the direction 

[112] 



PRIMITIVE BOOKS 

toward which the figures face, and that no uniformity 
existed in practice as to which direction that should be. 
It appears to have been a matter of indifference to the 
Egyptian scribes and readers whether they wrote and 
read from right to left, or from left to right. It would 
seem as if convenience would have established the cus- 
tom in favor of one direction or the other, but such seems 
not to have been the case. 

With the Babylonians, however, such a custom of 
writing always in one direction had been early inau- 
gurated. The character of the Egyptian writing, which 
consisted essentially of drawing pictures, made it per- 
haps equally convenient for the scribe to write in either 
direction. But this was not the case with the Babylonian 
and Assyrian writing, which, being made rapidly with the 
aid of a small stylus, could be much more conveniently 
carried forward from left to right — assuming the scribe 
to be right-handed — than in the opposite direction. 
Hence the method of writing from left to right gained 
universal prevalence. This method, as everyone knows, 
has the sanction of all European nations to-day. It is 
also used by the Ethiopians, but, curiously enough, it 
is not employed by such nations as the Arabians and 
Turks, who are of the racial stock of the Babylonians, 
nor by the Persians. Nor did the earliest Europeans 
adopt this direction of writing without cavil. Some of 
the oldest Greek and Roman inscriptions show a de- 
parture from any oriental model in that the writing 
runs in opposite directions in alternate lines, leading 
thus backward and forward across the page, in a way 
which suggested to the Greek mind the alternate fur- 

vol. vm. — 8 [ 113 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

rows of a ploughed field, and which, therefore, received 
the name of the boustrophedon or — in an awkward 
literal translation — oxwise. This plan had certain 
conveniences. The immediate contiguity of the end of 
one line with the beginning of the next makes it easy 
for the eye to follow on without danger of skipping. The 
reversed character of the letters and words of each al- 
ternate line is a little puzzling at first, but presents no 
difficulties to the practised eye. It is, at least, open to 
question whether this method might not have been 
adopted for the printed page, particularly where the 
lines are long, with distinct advantage. Be that as it 
may, however, the ancient scribe decided against the 
plan in course of time, and boustrophedon writing 
appears to have gone out of vogue altogether at 
least four or five centuries before the beginning of 
our era. 

It seems so natural for us to write from left to right, 
that the selection of this direction in preference to the 
other seems to call for no explanation. If explanation 
were required, the fact that the majority of scribes are 
right-handed seems an all-sufficient one. Yet, the 
equally familiar fact that the vast literature of Arabia, 
Turkey, and Persia, has been a continuous writ- 
ing in a flowing script that runs from right to left, 
robs this explanation of its plausibility, unless, indeed, it 
can be shown that the oriental scribes are either am- 
bidextrous, or left-handed; a suggestion for which there 
is, apparently, no evidence. Whatever the motives ac- 
tuating the selection, the fact remains that oriental 
writing as a rule is inscribed from right to left, occiden- 

[114] 



PRIMITIVE BOOKS 

tal, uniformly from left to right, and that each finds its 
prototype in the varied scripts of old Egypt. 

As regards the incidental aids to reading supplied by 
the separation of words from one another, the use of 
punctuation marks, of capitals, and of division into 
paragraphs, ancient writings, with very few exceptions, 
show a striking uniformity. To each and all of them, 
these expedients are quite unknown. The so-called 
determinatives at the end of Egyptian and Babylonian 
words give to the practised eye a clue that is equivalent 
to the space which we moderns always leave between 
words; but to the casual inspector of the writing, the 
signs and symbols appear to run on in an unbroken 
sequence. There is nothing to indicate where one word 
ends and the other begins. Neither is there any varia- 
tion in the type of letter to suggest the beginning of a 
sentence, or any mark of punctuation to indicate the 
end of a sentence or a shift in the phrase of thought. 
In short, the characters making up the text run on 
in an unbroken phalanx, from top to bottom of the page, 
and the better the manuscript is as a work of art, the 
more uniform and unvarying is the distribution of its 
characters. This applies, not merely to the oriental 
writings, but to the early Greek manuscripts as well. It 
is very puzzling, even to a person with a fair knowledge 
of the language, to attempt to decipher one of these con- 
tinuous scripts. Doubtless the readers of the time, 
having, of course, a perfect familiarity with their lan- 
guage, found no difficulty in reading such a script. Yet 
the real embarrassments that hamper such a system will 
be evident to anyone who will have the most familiar 

["Si 



SCIENCE IN THE INDUSTRIAL WORLD 

sentence in his own language written on a typewri- 
ter with the omission of spaces between the words. 
Hereisaprintedsampleinil lustration. The reader who 
stumbles a little over this sentence will be given a 
realizing sense of the difficulties that confronted a 
school-child of, for example, the Greek classical period. 

It goes without saying that the shift from the un- 
spaced, unpunctuated, unparagraphed sentence, to the 
modern method, was not made in a day or a generation. 
The study of a long series of manuscripts affords inter- 
esting illustrations of the slow invention of these con- 
veniences and the unreadiness with which a conserv- 
ative world adopted them. The old Persians were the 
only Orientals of antiquity who saw the desirability of 
indicating word divisions. Curiously enough, as it 
seems to us, they did not hit upon the plan of merely 
leaving a wider space at the end of words, but adopted, 
instead, the more laborious and less graphic method of 
placing an oblique line at a particular angle at the end 
of each word, — a line or, more accurately, a wedge- 
shaped mark differing in no respect, except in its angle 
of placement, from other marks that are variously 
grouped to make the characters of their writing. 

It will be recalled that the Persians divide with the 
Phoenicians the honor of the invention of an alphabetical 
writing. In the light of this fact, it is interesting to 
recall that one of the oldest pieces of writing in the 
Phoenician alphabetical script, namely, the inscription 
of the Moabite Stone, shows a tendency to mark with 
dots the divisions between words. It appears, from this, 
that the idea of the separation of words had occurred to 

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PRIMITIVE BOOKS 

scribes of a very early day. Why so convenient an ex- 
pedient, once suggested, should have failed of universal 
recognition, is food for conjecture. Whatever the ex- 
planation, it is a familiar fact that all the early Greek 
and Roman manuscripts are altogether guiltless of at- 
tempt at word separation, or of punctuation, and that 
tentatives toward the use of these convenient ex- 
pedients did not begin to show themselves until we 
come to manuscripts of the old Roman period. Indeed, 
it is not until about the tenth century of our era that the 
manuscripts of Europe give evidence of the general 
adoption of word-spacing, punctuation, capitalization, 
and paragraphing. 

As regards capitalization, indeed, the earlier writings 
afforded no opportunities, since the Greeks and Romans 
of the classical time and their successors of the early 
Middle Ages used capitals exclusively in writing their 
books. The development of small letters — the so-called 
minuscules — was a space-saving and time-saving in- 
vention of the monks of the seventh and eighth centuries. 
When the minuscule script had come into vogue, the 
capitals were retained at the beginnings of sentences, 
perhaps quite as much for their ornamental effect as 
for any other reason. And the same motive, perhaps, 
was instrumental in establishing the custom of para- 
graphing, but the need of word divisions and punctua- 
tion marks had made itself felt by scribes and readers 
who dealt with a language not their mother tongue, 
and these various accessories came in time to be re- 
garded as absolute essentials. 

The full elaboration of the system of punctuation 

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SCIENCE IN THE INDUSTRIAL WORLD 

marks now in vogue, was, however, a work of even 
more recent centuries. No manuscript, prior to the 
day of the printing-press, is punctuated in quite the 
modern fashion; but, for that matter, the popular 
method of punctuating varies a good deal from genera- 
tion to generation. Just at present, for example, the 
colon is very much less in evidence on the printed page 
than it was fifty years ago. 

But these are mere details. From a broader view 
it may be said that all of the modern aids to the reader 
had gained practically universal acceptance among the 
makers of books before the close of the Middle Ages. 
We have already seen that the books themselves at this 
period were almost exact prototypes of modern books 
as regards form and binding. Indeed, as already men- 
tioned, the early printers made an effort to duplicate the 
written book, and it may be added that it is sometimes 
difficult to tell, at first glance, whether a book of the 
fifteenth century is a specimen of early printing, or a 
very perfect example of the writing of a scribe. It does 
no harm to recall that the connoisseur of the period 
regarded the printed book precisely in the same light 
in which a modern connoisseur of painting regards a 
chromo — as a cheap, meritricious, inartistic imitation, 
not to be countenanced by a person of taste or culture. 



[118] 



VII 

THE PRINTING AND MAKING OF MODERN BOOKS 

THE discovery of the art of printing is only one 
of the score of important things whose discovery 
must be credited to the inhabitants of the Flow- 
ery Kingdom. Judged by the standard of time alone, 
these Orientals have the advantage of Western nations 
by at least a thousand years, and for even a longer 
period for aught we know to the contrary. And yet, 
curiously enough, the Chinese language, in which the 
printed words are formed by symbols instead of letters, 
is probably less adapted to the use of movable types for 
printing than almost any other. 

In point of fact it is not quite certain that the Celes- 
tials were familiar with the use of movable types, but 
there is no doubt that for many centuries before the 
discovery of printing in the West, it was customary in 
China to take impressions on paper from engraved 
surfaces. Certain books were engraved on slabs of 
wood and these slabs displayed in front of the uni- 
versities for the benefit of the students. The students 
either took the impressions of these slabs themselves, 
or had them taken for them, thus collecting pages of an 
actually printed book. Several paper prints made 
in this manner in the middle of the third century are 
said to be still in existence. 

["93 



SCIENCE IN THE INDUSTRIAL WORLD 

The method of making these printed blocks was most 
simple. The scribe wrote with ink upon thin, trans- 
parent paper, which was pasted face downwards upon 
the wooden surface to be engraved. The engraver 
then cut out all the spaces between the black marks, 
leaving the type surface of the manuscript, from which 
impressions could be taken. It is quite possible that 
some form of movable types also was used for purposes of 
printing at this time; but, as suggested a moment ago, 
the Chinese method of writing by symbols instead of by 
the use of an alphabet does not lend itself to the use of 
movable types as do the Western languages. And even 
to-day a great deal of the printing in China is done from 
engraved blocks not unlike the slabs used by the uni- 
versity students two thousand years ago. 

THE INVENTION OF PRINTING IN THE WEST 

It is not an easy matter to determine who was the first 
person in the European world to conceive the idea 
of printing from movable types. There are several 
claimants, most of them from among the people in the 
north of Europe; but it seems all but certain that the 
first book actually printed from movable types came 
from the shop of Johannes Gutenberg, of Mainz, 
Germany, about the year 1450. He is generally re- 
garded, therefore, as the " father of printing"; and 
despite the claims made on behalf of others, Gutenberg 
is likely to retain his place in history as the first printer. 

The book he printed was very appropriately the Bible ; 
and his press was about the simplest, as well as the first, 

[120] 



PRINTING AND MAKING OF BOOKS 

ever invented. It consisted of two upright timbers, 
stayed at the top and bottom with two cross-pieces. 
There were also two intermediate cross-pieces, the lower 
of which supported the flat "bed" upon which the 
types were placed, the upper being pierced by the screw 
which was attached to the " platen," or flat surface which 
is pressed down upon the type. In using this press the 
type was clamped into a frame called a "coffin," on the 
bed. It was then inked with a leather ball stuffed with 
wool, the paper laid on carefully, a piece of blanket 
placed over this to remove inequalities, and the platen 
screwed down hard by means of a hand lever working 
on the screw. Between each impression the platen 
was raised by reversing the motion of the lever, and 
the blanket and paper removed. 

This was a tedious process, and this kind of press 
about the simplest imaginable; yet it was neither 
changed nor improved upon for something over a 
hundred years, and it is responsible for the great flood 
of literature that spread over the Western world with 
such revolutionary effects during the fifteenth and six- 
teenth centuries. And while there is little resemblance 
between the great perfecting presses used in the large 
printing establishments to-day, and Gutenberg's little 
machine, there is no difference in the general principles 
of each. Indeed, the hand-presses now in use, and upon 
which the very finest cuts are made, are very like the first 
Gutenberg press, except that iron frames and metal 
parts have replaced those formerly made of wood. 

The process of development was a slow one, even 
after the first departure from the earliest type of press S 

[121] 



SCIENCE IN THE INDUSTRIAL WORLD 

was made. The first improvement was made by 
William Blaew, of Amsterdam, who improved the move- 
ment of the platen and simplified the work of manipu- 
lating the screw by a device for rolling in and out the 
bed, so that the platen need only be raised a short 
distance between impressions. This press soon became 
very popular all over Europe, and remained practically 
unchanged from its invention, in 1620, until the closing 
years of the eighteenth century. By that time the de- 
mand for more pressure upon the "form" caused the 
Earl of Stanhope to produce a press having a frame 
made of one piece of cast iron. He made several im- 
provements in the system of levers for working the 
platen, which were also very advantageous to the press- 
men. But his press was still only a modified Guten- 
berg press, as were those of Clymer, Rust, and Smith 
a little later; and the "Washington" press, which 
is even now the popular hand-press for taking fine 
proofs, is really only the perfected product based on 
all these models. 

By the end of the first quarter of the nineteenth cen- 
tury many improvements had been made in presses, 
particularly in the manner of applying power, the old 
hand-presses having practically disappeared except for 
the special work just referred to. The press invented 
by Isaac Adams, of Boston, in 1830 and in 1836 was a 
very popular one; and Hoe & Company, of New York, 
were busy in the preparation of presses that should meet 
the increasing demands of the newspapers for faster 
work. But as yet few of these presses departed very 
radically from the original idea of a flat platen pressing 

[122] 




AN EARLY TYPE OF PRIXTIXG-PRESS 



This Caxton printing-press, now in the Victoria and Albert Museum, London, is known 
to be two hundred years old, and is still in good working order. This type of press is still 
used for printing fine engravings. 



PRINTING AND MAKING OF BOOKS 

against a flat bed of type. The improvements had been 
largely in the mechanism for applying this pressure. 



THE CYLINDER PRESS INVENTED 

Early in the century an Englishman, William Nichol- 
son, conceived the idea of a press which, instead of 
having a flat platen or a flat bed, should have one, or 
possibly both, of these in the form of a cylinder, so 
that the paper, instead of being laid upon the forms 
and pressed, should be fed between cylinders, just as 
any material is fed to a rolling-machine. But Nichol- 
son, although he took out patents for his press, merely 
made drawings and plans without constructing a 
machine ; so that his attempts, although perfectly prac- 
tical as proved by later events, bore no fruit and he is 
not legitimately entitled to the credit of introducing 
the "cylinder press." 

The practical solution of the problem must be credited 
to the Saxon, Friedrich Koenig. With the assistance of 
a London printer by the name of Bensley, he devised a 
cylinder machine in 1812-1813, and printed several 
books upon it. In this machine "the form of type was 
placed on a flat bed, the cylinder above it having a 
threefold motion, or stopping three times; the first 
third of the turn received the sheet upon one of the 
tympans and secured it by the brisket ; the second gave 
the impression and allowed the sheet to be removed by 
hand, while the third returned the tympan empty to re- 
ceive another sheet." This machine worked well, and 
was followed later bv several other machines by the same 

[123] 



SCIENCE IN THE INDUSTRIAL WORLD 

inventor, among them a cylinder machine that printed 
on both sides of the paper, and was called a "perfecting 
press." 

At the same time that Koenig was working upon his 
presses several other inventors were producing machines 
on somewhat the same lines, most of these inventors 
being Europeans, America not having as yet entered the 
field with any serious competitor. Among these inven- 
tors was Napier, who produced a cylinder press which 
was equipped with grippers or "fingers" for the con- 
veyance of the sheets around the cylinder during the 
impression, and for delivering them after printing. 
This was about 1830, and the advantages of this press 
were so obvious that two years later Robert Hoe, of 
New York, sent over to England a young man, Sereno 
Newton, to study the workings of these presses. The 
ultimate result of this fortunate event was the well- 
known firm of R. Hoe & Company, of which Newton 
was a member. That name is now associated with 
printing-presses the world over. Almost from the day 
that this company came into existence the centre of 
manufacture began shifting from the old world to the 
new; and to-day the American printing-press stands 
without a rival. 

It should not be understood that the popularity of the 
American press was in the nature of a sudden mushroom 
growth. On the contrary the American manufacturers 
had struggled for half a century to compete successfully 
with their European rivals. But by the middle of the 
century they had overhauled them; by the end of the 
century they had completely outstripped them. A few 

[124] 



PRINTING AND MAKING OF BOOKS 

European presses occasionally make their way into this 
country from time to time, but the experiment is usually 
a costly one, as almost invariably they prove to be in- 
ferior to the home product. 

It should not be understood that the cylinder type of 
press was unknown in America before Napier's inven- 
tion. On the contrary the Hoe company had one on the 
market. But by combining European ideas with those 
already known, a cylinder press was soon produced, 
modified types of which are still in use, particularly in 
the book and pamphlet printing establishments. The 
development of the great rotary newspaper perfecting 
presses, that "do everything but talk," is another story 
that will be considered in a moment. 

The cylinder press in use at the present time for the 
finest kind of letterpress work is really an American 
improvement upon a French invention. This is the 
"stop cylinder" invented by Dutartre in 1852, and 
introduced into this country a year later by Hoe & 
Company, who very shortly improved upon it, adding 
to these improvements year by year until the result is 
the marvelous machine of the present time. The stop- 
cylinder press has been recently described as follows: 

"The type is secured upon a traveling iron bed, which 
moves back and forth upon friction rollers of steel, the 
bed being driven by a simple crank motion, stopping 
or starting it without noise or jar. All the running por- 
tions of this bed are made of fine steel as hard as it can 
be worked. The cylinder is stopped by a cam motion 
pending the backward travel of the bed, and during the 
interval of rest the sheet is fed down against the guides 

[125] 



SCIENCE IN THE INDUSTRIAL WORLD 

and the grippers close upon it before the cylinder 
starts, thus insuring the utmost accuracy of register. 
After the impression, the sheet is transferred to a 
skeleton cylinder, also containing grippers, which re- 
ceives and delivers it over fine cords upon the sheet 
flyer, which in turn deposits it upon the table. The 
distribution of the ink is effected partly by a vibrating, 
polished, steel cylinder, and partly upon a flat table at 
the end of the traveling bed, the number of form-inking 
rollers varying from four to six. This is without doubt 
the most perfect flat-bed cylinder printing-machine 
that has ever been devised." 1 

But this type of cylinder press, while able to pro- 
duce the best kind of work, is comparatively slow — 
too slow for the demands of the newspapers, which are 
forever crying for more speed. The best that the old- 
style cylinder press could do was only about two 
thousand impressions per hour, or about as fast as the 
feeder could lay the paper in place. This was of course 
altogether too slow, and a double-cylinder machine was 
tried, in which the bed was lengthened so that it was 
acted upon by two cylinders, and upon which two feeders 
worked. But even with this machine only four thou- 
sand sheets printed on one side could be produced per 
hour, and this was still far below the requirements. 

THE ADVENT OF THE " TYPE-REVOLVING MACHINE" 

It is a curious fact in the history of invention that 
great discoveries have frequently followed closely upon 
the announcement from authoritative sources that 

[126] 



PRINTING AND MAKING OF BOOKS 

such discoveries would be impossible. Indeed this ha9 
occurred so frequently that some one was prompted 
to remark recently that one reason why the practical air- 
ship had not been invented sooner was because every- 
body expected that it would be. "Let all the scientists 
come to the agreement that aerial flight is impossible, " 
said this cynic, "and very soon we shall fly.' , 

Be this as it may, it is certain that the invention of a 
printing-press with the type revolving on cylinders 
followed closely upon the statement by the world's 
leading journal that such a machine was mechanically 
impossible. "No art of packing could make the type 
adhere to a cylinder revolving around a horizontal axis 
and thereby aggravating centrifugal impulse by the 
intrinsic weight of the metal," said the London Times 
in December, 1848. Ten years later the same paper 
was being printed by a machine of this impossible kind, 
the invention of the American, Richard M. Hoe. 

It is perfectly obvious to anyone that there would be 
many advantages in a printing-machine to have the type 
arranged on the surface of a revolving cylinder which 
could be rotated continuously in one direction, printing a 
sheet at every revolution. But the difficulty, as The Times 
pointed out, lay in discovering some method of holding 
the type in place on such a machine. The imperative 
demands of the American newspapers, however, acting 
as a constant stimulus to inventors, caused them to 
make ceaseless efforts to produce such a machine, or 
one that would turn out more work ; but it was not until 
1846 that such a machine was perfected. In that year, 
a "Hoe Type-Revolving Machine" was placed in the 

[127] 



SCIENCE IN THE INDUSTRIAL WORLD 

office of the Philadelphia Ledger and soon demonstrated 
that a revolution in newspaper presses was at hand. 

The actual output of this, and other similar machines, 
was limited to the number of sheets of paper that 
could be fed to it by hand — about two thousand sheets 
per hour — just as in the case of the flat type-bed machine 
where the paper is carried on a cylinder. But the great 
advantage lay in the fact that several paper-bearing 
cylinders could be acted upon at each revolution of the 
type-bearing cylinder, each one fed by an operator 
at the rate of two thousand sheets an hour. A single- 
cylinder machine could produce two thousand sheets; 
but the same cylinder revolving at the same speed could 
be made to increase its capacity two thousand sheets 
for every additional cylinder and feeder. As many 
as ten of these paper-carrying cylinders were grouped 
around type cylinders, the output of such a machine 
being twenty thousand papers an hour. By means of 
these "ten-cylinder rotary' ' presses the newspapers 
were, for the first time, able to meet the demands of 
their rapidly increasing circulations, and the day of the 
"ten-minute edition" was in sight. 

Before these rotary machines had been perfected, 
however, another valuable discovery had been made. 
This was a method of casting stereotype plates on a 
curve. By this method it was possible to take duplicate 
impressions of the type, cast them as solid pieces of 
metal, and use them on the rotary presses just as the 
types themselves are used. In this manner a number of 
presses could be supplied with stereotypes made from a 
single setting of type, and requiring only the additional 

[128] 



PRINTING AND MAKING OF BOOKS 

time of casting a plate for each machine. In some of 
the newspaper offices of New York and London as 
many as five of these machines were operated at the 
same time. 

But still the capacity of these machines was limited 
to the possible speed of the hand feeders. The paper 
was fed in sheets cut to the proper size, and each one 
must be handled either by a human feeder or by some 
mechanical device. It was impossible to increase the 
speed of the printing cylinder, therefore, beyond the 
speed-capacity of the feeders. To overcome this defect 
several inventors began experiments with machines that 
would do away with feeders and single sheets of paper, 
printing from continuous rolls or "webs" of paper, and 
cutting off the paper into proper lengths after the im- 
pression had been made. 

To those unfamiliar with the subject, this under- 
taking would seem to be a comparatively simple one, 
consisting essentially of some device for cutting off 
the paper at definite intervals; but in practice many 
difficulties were encountered. First of all there was dif- 
ficulty with the inks, and ink-makers were urged to pro- 
duce rapid-drying and "non-setting-off" inks; and 
these were soon produced. Another difficulty was in 
obtaining paper in the roll of uniform strength and 
perfection ; but paper manufacturers, by giving special 
attention to the making of these rolls, soon produced a 
satisfactory product. But, curiously enough, the prob- 
lem of rapidly severing the paper was one of the 
most perplexing to the inventors, and was not solved 
until 187 1, in a new Hoe machine. In this the sheets 

vol. vin. — 9 [ 1 29 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

were not entirely severed by the cutters, but simply per- 
forated, and then drawn by accelerating tapes, which 
completely separated them, into a gathering cylinder so 
constructed that six perfect papers, or any other desired 
number, could be gathered one over the other. These 
were delivered to the receiving board by an ingenious 
device patented by Stephen D. Tucker, of the firm of 
Hoe & Company. 

The many advantages of this new machine were so 
apparent that the earlier types of presses were quickly 
discarded by the great newspaper offices. A London 
paper, Lloyd's Weekly Newspaper, headed the list, 
and was followed shortly by the Tribune in New York; 
while other papers soon followed their example. There 
seemed to be no limit to the printing capacity of these 
new presses except the ability of the paper to stand 
the strain. As many as eighteen thousand perfected 
papers could be turned out in an hour, although the 
average was usually a few thousand less than this. 

It was not until 1875, however, that a satisfactory 
folding device was perfected. Until that time the ex- 
treme limit of the folders in use was eight thousand 
papers an hour; but in that year Stephen D. Tucker 
again came forward with an invention, a rotating fold- 
ing cylinder, that folded papers as fast as the presses 
could print them. 

It would seem by this time as if the ingenuity of press 
inventors must be exhausted, and that the " perfecting' ' 
press was as nearly " perfected" as possible. But this 
was by no means the case. A paltry output of fifteen 
thousand carefully folded newspapers per hour for a 

[130] 



PRINTING AND MAKING OF BOOKS 

press was far from satisfactory, and soon new presses 
were produced that trebled this capacity. Thus the 
press placed in the office of the New York World, in 
1887, had a capacity of forty-eight thousand papers 
an hour, "all delivered with great exactness and per- 
fection, cut at the top, pasted and folded ready for 
the carrier or the mails." 



A MODERN NEWSPAPER PRESS 

Four years later a new Herald press eclipsed even 
this monster. It required eighteen months for the con- 
struction of this press, which was composed of about 
sixteen thousand separate pieces. It was described in 
the New York Herald of May 10, 1891, in part as 
follows: 

"The new Hoe press which is being set up in the 
Herald Building is nothing less than a miracle of 
mechanism. To say that it is the only one of its kind 
ever built and that it throws all previous inventions into 
the background are facts which the following figures 
abundantly prove. 

" Its consumption of white paper is so astonishing that 
even the imagination grows tired and sits down to catch 
its breath. It is fed from three rolls, each being more 
than five feet wide. When it settles down to show its 
best work it will use up in one hour nearly twenty-six 
miles of this paper, or to make the matter more signifi- 
cant, it will use up about fifty- two miles of paper the 
ordinary width of the Herald every sixty minutes. 

"Our readers will be startled to learn that it can 

[131] 



SCIENCE IN THE INDUSTRIAL WORLD 

print and fold ninety thousand four-page Heralds in an 
hour. This is, to the mind which is not versed in the 
problem of rapid printing, a feat which makes Aladdin's 
lamp an old woman's fable. Ninety thousand per hour 
means fifteen hundred copies per minute, or twenty-five 
copies for every second ticked off by the clock in 
Trinity's steeple. 

"This press will print, cut, paste, fold, count, and 
deliver 72,000 eight-page Heralds in one hour, which is 
equivalent to 1200 a minute and twenty a second. 

"It will print, cut, paste, fold, count, and deliver 
complete 36,000 sixteen-page Heralds in one hour, which 
is equivalent to 800 a minute and a fraction over thir- 
teen a second. 

"It will print, cut, paste, fold, count, and deliver com- 
plete 24,000 fourteen-, twenty-, or twenty-four-page 
Heralds an hour, which is at the rate of 400 a minute, 
or very nearly seven a second. 

"This is lightning work with a vengeance, and yet 
it is possible that there may be some who read this who 
will live to call it slow . That will probably be when they 
have found all about how to put a harness on electric- 
ity. No one can predict when inventive genius will 
reach its limit in the printing-press. But for the present 
this new press marks high- water mark. 

"The new press has a well-nigh insatiable appetite 
for white paper. To satisfy it, it is fed from three 
rolls at the same time, one roll being attached at either 
end of the press and the third suspended near the centre. 
Each roll is sixty-three inches wide, or twice the width of 
the Herald. When doing its best this press will consume 

[132] 



PRINTING AND MAKING OF BOOKS 

25 J miles of sixty- three-inch- wide paper — equivalent 
to 5 if miles of paper the width of the Herald — in one 
hour and eject it at the two deliveries. It is a sight worth 
seeing to see it done. Certainly we know of nothing else 
which affords such a striking example of the triumph of 
mechanical genius. 

"A man turns a lever, shafts and cylinders begin to 
revolve, the whirring noise settles into a steady roar, 
you see the three streams of white paper pouring into 
the machine from the three huge rolls, and you pass 
around to the other side — it is literally snowing news- 
papers at each of the two delivery outlets. So fast does 
one paper follow the other that you catch only a momen- 
tary glitter from the deft steel fingers that seize the 
papers and cast them out. 

"The machine weighs about fifty-eight tons. It is 
massive and strong with the strength of a thousand 
giants. And yet though its arms are of steel and its 
motions are all as rapid as lightning, its touch is as 
tender as that of a woman when she carries her babe. 
How else does the machine avoid tearing the paper? 
It tears very readily, as you often ascertain accidentally 
when turning over the leaves. Truly wonderful it is, 
and mysterious to anybody but an expert, how this 
huge machine can make newspapers at the rate of 
twenty-five a second without rending the paper all to 
shreds. 

"It has six plate-cylinders, each cylinder carrying 
eight stereotype plates which represent eight pages of 
the Herald, and six impression-cylinders These cylin- 
ders, when the press is working at full speed, make 



SCIENCE IN THE INDUSTRIAL WORLD 

two hundred revolutions a minute. The period of 
contact between the paper and the plate-cylinders is 
therefore inconceivably brief, and how in that fractional 
space of time a perfect impression is made, even to the 
reproduction of such fine lines as are shown in the illus- 
trations, is one of those things which, to the man who is 
not 'up' in mechanics, must forever remain a mystery. 
But that it does it you know, because you have the evi- 
dence of your own eyes. 

"A double folder forms part of this machine. A 
single folder would not be equal to the task imposed upon 
it. As it is, this double folder has to exercise such celer- 
ity to keep up with the streams of printed paper that 
descend upon it that its operations are too quick for the 
eye to follow. 

"The press has two delivery outlets. At each the 
papers are automatically counted in piles of fifty. No 
matter how rapidly the papers come out, there is never 
a mistake in the count. It is as sure as fate. By an 
ingenious contrivance — if I should attempt to describe 
it more definitely most people would be none the wiser — 
each fiftieth paper is shoved out an inch beyond the 
others that have been dropped onto the receiving tapes, 
thus serving as a sort of tally mark. 

"Truly it is a marvelous machine — this sextuple 
press. Nowhere will you find a more perfect adaptation 
of means to ends; nowhere in any branch of industry 
a piece of mechanism which offers a finer example of 
what human skill and ingenuity is capable of." 

From this it will be seen that at least one desideratum 
of the printing-press, speed, had been attained. But 

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PRINTING AND MAKING OF BOOKS 

there was still much to be desired in the way of quality 
of work. A hundred thousand folded and pasted news- 
papers could not be turned out by a single machine every 
hour without great sacrifice in quality of the presswork. 
And yet the quality was marvelously good, all things 
considered. So good, indeed, as to warrant the belief 
that it was simply a question of perfecting the details of 
the existing rotary presses to make them produce letter- 
press of "magazine" quality. In fact, while the great 
press just described was under construction, the same 
builders were planning another marvel, which should do 
for the magazines what had been done for the newspaper. 
How well they succeeded is attested by the fact that the 
new press was requisitioned for doing the plain forms 
of one of the best printed periodicals in the world, by 
the master-printer, Theodore L. DeVinne, whose 
reputation as a printer rests upon the excellent quality 
of his work. 

A PERFECTED MAGAZINE PRESS 

In an article contributed to the Century Magazine 
Mr. De Vinne described this new press as follows : — 

"At the end of a long row of machinery," he says, 
"stands the web press — a massive and complicated con- 
struction, especially built by Hoe & Company, for 
printing, cutting, and folding the plain and advertising 
pages of the Century. Web presses for newspapers are 
common enough, but this press has the distinction as the 
first, for good book- work. At one end of the machine is 
a great roll of paper more than two miles long when 

[135] 



SCIENCE IN THE INDUSTRIAL WORLD 

unwound, and weighing about 750 pounds. As the paper 
unwinds it passes first over a jet of steam which slightly 
dampens and softens its hard surface and fits it for re- 
ceiving impressions, without leaving it wet or sodden. 
It passes under a plate-cylinder, on which are thirty- 
two curved plates, inked by seven large rollers, which 
print thirty-two pages on one side. Then it passes 
around a reversing cylinder which presents the other 
side of the paper to another plate-cylinder, on which 
are thirty-two plates which print exactly on the back 
the proper pages for the thirty- two previously printed. 
This is done quickly — in less than two seconds — but 
with exactness. To do this it is drawn upward under a 
small cylinder containing a concealed knife, which cuts 
the printed web in strips two leaves wide and four leaves 
long. As soon as cut the sheets are thrown forward 
on endless belts of tape. An ingenious but undetecta- 
ble mechanism gives to every alternate sheet a quicker 
movement, so that it falls exactly over its predecessor, 
making two lapped strips of paper. Busy little adjusters 
now come into play, placing these lapped sheets of 
paper accurately up to a head- and a side-guide. With- 
out an instant of delay down comes a strong creasing 
blade over the long center of the sheet and pushes it 
out of sight. Pulleys at once seize the creased sheet and 
press it flat, in which shape it is hurried forward to meet 
three circular knives on one shaft, which cut it across in 
four equal pieces. Disappearing for an instant from 
view, it comes out on the other side of the upper end of 
the tail of the press in the form of four folded sections of 
eight pages each. Immediately after, at the lower end 

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PRINTING AND MAKING OF BOOKS 

of the tail of the press, out come four entirely different 
sections of eight pages each. This duplicate delivery 
shows the product of the press to be at every revolution 
of the cylinder sixty-four pages, neatly printed, truly 
cut, and accurately registered and folded, ready for the 
binder. 

"Two boys are kept fully employed in seizing the 
folded sections and putting them in box trucks, in 
which they are rolled out to the elevator, and on these 
sent to the bindery. This web press is not so fast as 
the web press of daily newspapers, but it performs more 
operations and does more accurate work. It is not a 
large machine, nor is it noisy, nor does it seem to be 
moving fast, but the paper goes through the cylinders at 
the rate of nearly two hundred feet a minute. It does 
ten times as much work as the noisier and more bustling 
presses by its side." 

The fact that so exacting a master-printer as De Vinne 
was satisfied with the work of the new rotary press stim- 
ulated the press manufacturers to produce a rotary press 
that could be used, not only for the plain parts of maga- 
zines, but for woodcut and half-tone illustration print- 
ing. As a result the "Rotary Art" press was put into 
operation within a few months after the press just de- 
scribed, turning out as good work of all kinds as can be 
done by stop cylinder, or hand-press. 

But even this triumph does not close the chapter of 
progress in printing. In one-color printing, to be sure, 
there is little left to be done, for speed and quality of 
the presswork are verging on what we may be allowed 
to call perfection, judged by modern standards. But 

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SCIENCE IN THE INDUSTRIAL WORLD 

there is still the enormous field of color printing, that 
is now only in its infancy. "The demand for printed 
matter seems to increase with the ability to furnish it," 
says a recent writer, "and much attention is now being 
directed to the subject of color printing on the rotary 
system. From present appearances and from the en- 
terprise displayed by the publisher, the artist, and the 
press-maker, it would seem as though the day is not far 
distant when this subject alone would furnish matter 
for a new chapter in the history of the printing-press. ,, 

And, indeed, for anything but the very finest kind of 
color printing, the matter for this chapter is already 
in hand. In a later chapter in this volume this subject 
will be again taken up in detail with particular reference 
to the scientific aspects of the color combinations; but, 
as will be seen there, the matter of perfection is really 
"up to" the presses, and they are making strides that 
are certain shortly to close the gap. 

"The last three or four years have witnessed an im- 
mense advance in the art of color printing. The maga- 
zine without an elaborate color cover, or perhaps colored 
illustrations, is now an exception, whereas it was the 
reverse not long ago. After satisfactory experiments 
it was ascertained that, with the inks properly prepared, 
and suitable plates to print from, colors could be 
printed almost simultaneously upon the paper, without 
mingling; in short, that the supposed necessity, in 
much of the work done, of drying the sheets after the 
impression of each color on the paper, was not necessary 
for the production of a good quality of printing. Fur- 
ther experiments also proved the mechanical possibility 

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PRINTING AND MAKING OF BOOKS 

of obtaining most accurate register in printing from the 
roll, and that the number of impressions, or colors, could 
be increased to advantage.'' At the present time these 
great rotary color-printing machines have been brought 
to a stage of perfection so that from ten to twelve colors 
are now printed at a single journey through the press, 
at the rate of about 100,000 copies an hour. 

OTHER AIDS TO THE PRINTER 

It should not be understood that it was simply in 
the matter of presses that the publishing world made 
giant strides of progress in the latter half of the nine- 
teenth century. Indeed, had there not been a cor- 
respondingly rapid development in other fields, the 
great rotary presses would have been of little account. 
For such presses must be fed, not only with paper and 
ink, but with ever changing type, which, if set by the 
slow hand-method, piece by piece, would not keep the 
greedy rotary monsters supplied. But fortunately the 
invention of devices for setting type rapidly was keep- 
ing pace with the capacity of the presses to use them. 

As everyone knows, the old method of setting type — 
the only one known until two decades ago — was that 
of picking out each individual type by hand, and plac- 
ing it in a certain position on a special device for holding 
it, called a " stick." The limit of speed of type-setting, 
therefore, was governed by the capacity of the indi- 
vidual type-setter, or the number of men employed. 
There was no means of hastening the process except 
by increasing the number of men. But with the im- 

[i39] 



SCIENCE IN THE INDUSTRIAL WORLD 

provements in the presses, and the demand for constantly 
changing "copy" in the different editions of the daily 
papers, the hand-setting methods were found to be a 
constant drag. It was not until early in the '8os, 
however, that any mechanical aids were devised. 
But since that time type-setting and composing ma- 
chines have almost completely supplanted hand-setting 
methods. 

The different kinds of machines that have taken the 
place of hand setting all fall into one of three general 
classes. There are those in which ordinary types are used, 
but in which the setting is done by the aid of a key- 
board working in much the same manner as the ordinary 
typewriter keyboard, the pressure of each key setting 
in motion machinery that places the corresponding type 
in its place on the stick. There are also machines in 
which no type is used, the letters being formed on a bar 
by the manipulation of a keyboard, and cast in slugs 
of one line each, so that the operator literally casts his 
type as he goes along. And there is still a third class, 
quite as wonderful, with which the operator uses a 
machine provided with a keyboard, the letters of which, 
when depressed, punch holes in a roll of paper. This 
roll is then placed in a steam-driven machine which 
interprets the holes in the strip of paper into type 
corresponding to the keys depressed by the operator, 
casting them one by one at the rate of something like 
a hundred a minute, and placing them in position 
ready for the presses. 

Each of these classes of machines has its advan- 
tages and disadvantages, which may be considered for a 

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PRINTING AND MAKING OF BOOKS 

moment before examining the individual machines in 
detail. The type-setting machines proper, in which 
ordinary types are used, labor -under the disadvantage 
that they have to be "loaded" with type before they can 
be operated; and until recently these types had to be 
re-distributed after the printing was done. But the im- 
portance of this defect has now been lessened by the 
invention of marvelous type-casting machines, which 
cast over a thousand types a minute, placing them in 
such position that they can be loaded into the type- 
setting machine ready for action in a few seconds. 
This can be done so cheaply that it no longer pays to 
distribute the type after it is set, a new dress of type 
being used every time printing is done. This kind of 
type-setting and type-casting machines is in use in some 
of the largest printing offices in the world, particularly 
in Europe. 

The machines that make their types, or slugs that 
correspond to types except that they are in one-line 
lengths instead of single types, are those known as 
" linotype" machines. These have so many advantages 
over ordinary single type-setting machines that they 
are very properly the most popular machines for certain 
kinds of work, particularly where speed rather than ac- 
curacy is the desideratum. The disadvantage of 
these slug-machines is that if a mistake is made any- 
where in one of the lines, the entire line must be made 
over again, instead of being corrected in the ordinary 
manner. For this reason, where there are likely to be a 
great number of corrections, as in the case of authors' 
manuscripts, the final cost of composition with lino- 

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SCIENCE IN THE INDUSTRIAL WORLD 

type machines may be greater even than handwork. 
Where there is no necessity for numerous corrections, 
however, the linotype setting is probably the best, and 
the cheapest, of any of the mechanical type-setting 
processes. 

The kind of machine that makes its own types auto- 
matically and individually from holes punched in 
strips of paper, such as the Lanston monotype machine, 
has practically all the good features, and very few of 
the bad ones, of the other two. It is a relatively delicate 
mechanism, however, and for this reason much more 
liable to get out of order than either of the other 
machines. Nevertheless, the monotype machines have 
practically superseded all others for the fine class of 
work formerly done by hand. 

Both the linotype and monotype machines are such 
marvels of ingenuity that they are worth considering 
somewhat in detail. As they have been described re- 
cently by an eminent authority on the subject, I take 
the liberty of quoting him in part here. 

THE MERGENTHALER LINOTYPE 

"The linotype machine, invented by Ottmar Mergen- 
thaler, of Baltimore, Maryland, became commercially 
successful during the early '90s. The machine is 
less than five feet square, and weighs about two thousand 
pounds. It consists of a bank of keys connected with a 
magazine containing about fifteen hundred brass 
matrices — small plates about an inch wide — the thick- 
ness varying with the type character. On one edge is 

[ T 42 ] 



PRINTING AND MAKING OF BOOKS 

the die from which is cast the letter, and at the upper 
end are a series of nicks or teeth for distributing pur- 
poses, and every character possesses a different combi- 
nation. Each magazine contains a number of matrices 
for each letter, and all the usual characters required 
by a complete font of type, together with spaces, quads, 
etc., of varying thicknesses. In addition there are also 
flat, elongated, wedge-shaped spaces which are inserted 
between words and employed for justifying each line 
as it is cast. 

"The magazine containing the matrices is an inclined 
receptacle two feet six inches high, the top being about 
six feet from the floor. Within this magazine are 
channels in which the matrices for the different letters 
are stored, and through which they pass. The machine 
is so adjusted that as the keyboard is manipulated the 
matrices are selected in the order in which they are to 
appear in the slug or casting. When a key is depressed, 
the matrix to which it corresponds emerges from its 
channel, is caught upon an inclined traveling belt, and 
is then carried to the assembler, or stick. As each word 
is completed, a stroke of the space-key inserts the wedge- 
shaped space used between each two words. When 
the line is completed the operator can correct errors 
by extracting matrices or substituting other for those 
which are in the line. The wedge-shaped spaces are now 
pushed up through the line, securing instantaneous and 
complete justification. The completed line is then 
transferred automatically to the front of a mold ex- 
tending through a mold wheel at the left. Behind the 
mold is a melting-pot, heated by gas or gasoline, and 

[143] 



SCIENCE IN THE INDUSTRIAL WORLD 

containing molten metal. Within the pot is a pump- 
plunger leading to a perforated mouth arranged to close 
the rear of the mold. When the matrix line is in posi- 
tion the automatic operation of the plunger forces the 
metal into the mold and against the line of matrix letters, 
where it instantly solidifies in the form of a slug. The 
mold wheel then makes a partial revolution, bringing the 
mold in front of a blade which pushes the slug into a 
receiving galley, ready for the proof press. 

" Having served their purpose in front of the mold, the 
matrices are returned to the magazine to be utilized 
in new combinations. The distribution is accomplished 
automatically. The operation of the machine permits 
the composition of one line, the casting of a second, and 
the distribution of a third to be carried on simultane- 
ously. The casting operation can also be arranged to 
work independently of the rest of the machine. It is 
said that this machine is capable of a speed greater than 
that at which the most skilful expert can operate the 
keys. The average product of a good operator is 4000 
ems per hour. Many operators, however, can produce 
from 5000 to 6000 per hour, and a speed of 13,000 is on 
record.' ' 

There is another machine, known as the "monoline," 
that is operated in much the same way as the linotype. 
In this machine "as the keys are struck on the key- 
board the matrices and spacers descend into the as- 
sembling box, traveling a distance of about four inches, 
and the bars are dropped more or less, according to the 
position of the letter to be brought in line to be cast. 
When the line has been completed to approximately its 

[i44] 



PRINTING AND MAKING OF BOOKS 

full length, the operator strikes a lever at the right of the 
keyboard, and begins the composition of the second line, 
while at the same time the machine automatically justi- 
fies the first line, carries it to the casting-pot, delivers 
it upon the galley, and returns the matrices and spacers 
to their respective receptacles in the magazine. The 
machine will not cast a line that has not been properly 
justified" — that is, the lines made even in every way. 

THE LANSTON MONOTYPE MACHINE 

"The Lanston monotype machine was invented by 
Tolbert Lanston, in 1886, but was not placed on the 
market until more than ten years later. The principle 
upon which it is constructed differs radically from that of 
the linotype. The monotype produces single types cast 
in the order of their use, and set in automatically justi- 
fied lines. It consists of two machines — a perforating 
device operated by a keyboard, and a casting machine. 
The keyboard differs from that of a typewriter only in 
the much greater number of characters, of which there 
are two hundred and twenty-five, comprising a complete 
font, including italics and small capitals. The keys 
are arranged in fifteen columns of fifteen rows each, 
with two extra rows at the top to secure justification. 
For each series of characters in the font a different color 
is used, so as to distinguish italic from roman fonts, etc. 
The keyboard is between three and four feet from 
the floor and is supported by an iron bar upon a base 
one foot square. At the top of the machine is a roll 
of paper which unwinds from one spool and winds on 

VOL. VIII. — IO [ 14^ ] 



SCIENCE IN THE INDUSTRIAL WORLD 

another as the keys are struck, and also a paper scale 
for registering the body-size of the type. 

"Before beginning his task, the keyboard operator 
sets an index of the number of ems required per line. 
Each stroke of a key perforates the paper ribbon in 
such a combination as to control the matrix of the 
proper letter in the casting machine, and causes the 
registering scale to charge to the line an amount equal 
to the body-width of the type just selected. In this 
way a line of matter is progressively perforated and 
charged until, as the end is approached, the line- 
scale shows that the next word or syllable cannot go 
into that line, while another portion of the registering 
scale indicates the amount of unfilled space in the 
line just perforated if it should be cast with its spaces 
of normal body size. Still another portion of the scale 
has been keeping account of the number of spaces 
used between words of the line, which may be varied 
in the process of justification. The machine thus 
mechanically notes for the operator the amount of 
space to be added, and the number of space-types 
among which the variation from the normal body- 
width may be apportioned. At the completion of 
each line the operator, by merely noticing the figures 
shown by the pointer on the justifying scale, knows at 
once what additional holes to perforate in the record 
in order to secure perfect justification. When he 
has touched the justifying keys the registering scale 
points to zero, advancing again as the new line 
progresses. These operators are all automatic. 

"From the perforator the spool passes to the casting 

[i 4 6] 



PRINTING AND MAKING OF BOOKS 

and setting machine — an intricate piece of mechanism 
about four feet high and slightly less in width, weighing 
about twelve hundred pounds. On being placed in the 
casting machine the ribbon is unwound in reverse order, 
the operation of casting and setting proceeding in like 
manner. The control of the casting machine by the 
perforations in the ribbon is effected by the pressure of 
air passing through the holes as the ribbon moves over a 
rounded plate. Within this plate are thirty-two air- 
tubes, and, as different perforations appear, different 
connections are made through these tubes with the 
working parts of the casting machine, a pressure of 
eight pounds being maintained. The two hundred and 
twenty-five matrices are contained in a die case measur- 
ing about three inches square. The matrix case shifts 
its position according to the kind or combination of 
perforations passing over the air- tubes. The perfora- 
tions for justification regulate the casting of space- 
types between words, causing the mold to be opened 
in a degree indicated by the justifying holes, in order that 
the space-types may be cast of the proper size. Thus 
from the record ribbon made at the keyboard, the cast- 
ing machines cast type and insert mathematically correct 
spaces at constant speed which may be kept up to the 
limit of cooling metal. It is the work of only a few mo- 
ments to remove one matrix case and substitute another. 
Moreover, the molds in which the bodies of the types are 
cast, also may be exchanged at short notice. 

"At one side of the casting machine is a melting-pot, 
in which an automatic plunger forces the hot metal into 
a nozzle leading directly to the mold upon which the 

[147] 



SCIENCE IN THE INDUSTRIAL WORLD 

matrix rests. The metal is forced against the matrix, 
which is filled first, and then instantly occupies the body 
of the mold under pressure, insuring a good cast. When 
chilled, the types are ejected through the mold into the 
carrier, which carries them to the line in the galley. 
As each line is completed, it is advanced automatically 
to make room for the next. The correction of matter 
set on the Lanston machine is the same as in hand com- 
position; it is not necessary to recast a line, as in the 
slug machines. 

"It should be observed that the keyboard and cast- 
ing machine have no connection whatever, and that 
each part can be operated independently. A keyboard 
operator can set matter as rapidly as he can read the 
copy and strike the keys, a speed of 5000 ems per hour 
being regarded as a moderate average. The type- 
casting machine casts and produces, according to the 
body size, from 75 to 125 ems per minute, or from 4000 
to 5000 per hour." 

From this it will be seen that this machine is a marvel 
of ingenuity. Yet, despite its complexity, it is entirely 
practical, and is undoubtedly the favorite composing 
machine at the present time. It may interest the reader 
to know that the pages of the present volume were com- 
posed on Lanston machines. The beauty and clearness 
of type and the evenness of justification speak for 
themselves. 

THE GRAPHOTYPE 

The Lanston has a rival, however, that has recently 
been placed upon the market, which is so simple, and 

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PRINTING AND MAKING OF BOOKS 

has so many features in common with the ordinary type- 
writer, that it is peculiarly attractive. This machine is 
known as the "graphotype" and differs from the other 
machines just described in that it is run by electricity. 

It is the invention of J. H. Goodson, who placed it up- 
on the market in 1899. "It is composed of two parts; 
a small table about the size of a typewriter desk, con- 
taining an ordinary typewriter, a perforating machine, 
and a small dial similar to a clock; and a caster and 
setter. The typewriter is in all respects unaffected as 
far as facility in writing is concerned. The operator is 
required, in addition to the execution of ordinary type- 
writing, to notice, when the end of the line is reached, 
the dial which controls the spacing, and to touch the 
key indicated by the dial, thus automatically spacing 
and justifying the line. 

"Each time a key is touched, not only is the proper 
letter written, but an electrical communication is made 
with the perforator, which perforates a narrow paper 
ribbon in a series of round holes so arranged that when 
the ribbon is placed in the casting and setting machine, 
a similar electrical connection is made through this 
perforation, by indicating the letter or space to be cast 
and set. The advantage of a visible, typewritten sheet 
is obvious. It is accessible to the operator for reference, 
and it may be read by the proof-reader instead of the 
first proof, as the type and the typewritten page are 
identical so far as the orthography is concerned. The 
ribbon, together with the corrected typewritten sheets, 
may be put away indefinitely for reprint or for possible 
use in the future, without expense for retaining metal." 2 

[i49] 



SCIENCE IN THE INDUSTRIAL WORLD 

TYPE-SETTING MACHINES 

It would seem that there would be little call for type- 
setting machines proper — that is, machines that actually 
set the types themselves instead of making them as they 
go along — once the monotype and linotype machines 
were invented; and in America such machines are not 
popular. But in Europe they are preferred by some of 
the largest and most progressive printing houses. The 
fact that type-casting machines have been brought to 
such a high stage of perfection, and that the types can 
be filled into the magazines of the type-setting machines 
automatically, has made it possible for these machines to 
compete at all. Yet there is unquestionably one decided 
advantage in this kind of machine: the operator has 
the composing stick, with the type falling into place, 
directly in view, so that he can read and correct mis- 
takes as he goes along. In this way he is able to turn 
over to the pressmen more nearly perfect copy than is 
possible with either of the other machines. 

Despite these slight advantages of the type-setting 
machines, however, it is probably right to regard them 
as obsolescent — as the highest representatives of a 
mechanical system that has been superseded by an 
entirely different and better one. Electricity is certain 
to come more and more into use as in the case of the 
"graphotype," just described, and with the simplifying 
of mechanisms that is sure to follow, machines that make 
and set their type at the same time are sure to gain in 
popularity. Nevertheless it would be unjust to the 
type-setting machines, which are marvels of ingenuity, 

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PRINTING AND MAKING OF BOOKS 

to pass them on without a more detailed description of 
one of the well-known makes. There are several which 
work perfectly and apparently with equal efficiency, 
but the Dow machine may be taken as a representative 
type. 

This machine consists of two parts, a composing 
machine for setting the type, and a distributing machine, 
the mechanism and operation of which have been 
described as follows: "The composing machine is a 
little over six feet high, and weighs about two thousand 
pounds. It is operated by means of a keyboard similar 
to that of a typewriter, but with ninety characters. 
The keys descend only three thirty- seconds of an inch, 
and are used simply to release certain parts, the driving 
power of the machine accomplishing the rest of the 
work. For greater ease in handling, the main type- 
magazine is divided into two parts. In the type 
channels, which are four feet in length, the types lie 
with their faces in sight, resting on their sides in order 
that a large number may be placed in one channel. 
For further increase of capacity, additional channels 
are devoted to letters in frequent use. 

"At each touch of the keyboard a single type is 
pushed from the magazine and advanced to a type 
raceway in front of, and parallel with, the magazine. 
This raceway, which is in a continuous horizontal line, 
widens at one end, so that as the type enters and is 
pushed along by a rapidly reciprocating type-driver, it 
is stopped at the center by the narrowing of the race- 
way. From this it is conveyed into an upright channel 
or "stick," each type forcing down the preceding one. 

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SCIENCE IN THE INDUSTRIAL WORLD 

As the types enter the stick their faces are presented 
directly in view of the operator, who can read and cor- 
rect them at will. A bell gives warning when a line is 
approaching completion, and a gage at the side of the 
channel in which the line of type is formed, shows how 
much the line is short or how far the operator has over- 
run the standard measure he is setting. When the line 
is full the operator touches the line key, and then with- 
out further attention on his part, and without delaying 
the composition of the next succeeding line, the stick 
of type turns half-way round and the line of char- 
acters is thrust by a blade to a point on the raceway 
called the " bridge," where the process of justification 
begins. 

"The Dow distributor is entirely separate from the 
composing machine, but its mechanism is of the same 
positive character. The operation by which it distrib- 
utes the various types in their respective channels is 
automatic, and allows a normal speed sufficient to supply 
three composing machines with type. For purposes of 
distribution the body of each type-character has a 
special identifying nick. The distributor, which lies 
flat, consists of a central disk joined to a set of channels 
radiating like a fan. Upon the periphery of the disk are 
supported thirty-six type-carriers, and as these are 
rotated past the galley channel on one side, each re- 
ceives a single type, which is carried round until it 
is opposite the proper channel, when it is pushed out 
of the carrier into the channel, the distributor continu- 
ing its rotation." 7 

[152] 



PRINTING AND MAKING OF BOOKS 

BOOKBINDING 

No better example of how necessity has stimulated 
invention is known than that of the development of 
bookbinding. When the only method of making books 
was the tedious process of writing them, the bookbind- 
ing methods were correspondingly deliberate. When 
printing was introduced, bookbinders discovered new 
materials and methods, and were soon able to keep 
pace with the production of printed sheets. And when 
the great advance in the methods of mechanically setting 
type and reproducing pictures was made a quarter of a 
century ago, which for the moment seemed to threaten 
to flood the market with more printed material than the 
bookbinders could handle, the binders responded with 
inventions of automatic machinery that could put covers 
on books as fast as the printers could supply them. 

It is an interesting thing that, while the changes in 
making book-covers and in bookbinding have undergone 
so many revolutions, the shape of the finished volume 
has remained practically unchanged for a thousand years. 
The books of the ninth century which are still preserved 
are practically the same shape as those made to-day. 
The scroll, folded book, fan-leaved book, and probably 
a number of other forms had all been tried in preceding 
centuries; but the ideal form — leaves bound between 
two covers and free upon three edges — was attained, 
as we have seen, over a thousand years ago, and has 
never been improved upon. 

In point of luxuriousness the modern book-cover is 
sadly degenerate. Covers are still made of costly ma- 

[153] 



SCIENCE IN THE INDUSTRIAL WORLD 

terial — silks and fine leather, and gold, and "pearl" 
trimmings — but the covers with clusters of precious 
gems, with gold hinges, clasps, and locks, and delicately 
carved ivory, have passed away with the other relics 
of the Dark Age. And yet the cover of the modern book, 
as in the case of the medieval tome, is usually the most 
costly part of the volume. The relative values have 
probably changed very little, for the manuscript volume 
was expensive. 

In medieval times, and indeed until well into the eight- 
eenth century, wood was the favorite material for the 
sides of book-covers. Some of these covers of the early 
period, with "their metal hinges, bosses, guards, and 
clasps, seem, in all but dimensions, fit for church doors. " 
But as soon as the printing-press came upon the scene 
this heavy type of cover was replaced by lighter and less 
clumsy ones. At first these were still made of thin 
boards, covered with leather or cloth; but as the art of 
manufacturing paper became better understood, this 
substance gradually replaced all others. 

For several centuries after the invention of the print- 
ing-press the whole process of bookbinding was done by 
hand. The sheets were folded by hand as they came 
from the presses, sorted, and sewed together by hand. 
The covers were made practically without the aid of 
any machinery, so that frequently the reputation of a 
bookbinder rested entirely upon his individual manual 
dexterity. Artistic taste also entered into the estimate, 
and upon a combination of these qualities rests the 
fame of the early binders such as Grolier, Le Gascon, 
Pasdeloup, Derome, and, later, the Englishman Roger 

[iS4] 



PRINTING AND MAKING OF BOOKS 

Payne. And it is only within the last generation that 
machinery has completely supplanted the older hand- 
methods. Indeed, the giant strides toward mechanical 
perfection and automatic action in bookbinding 
machinery were not made until the very end of the last 
century. 

In many ways, perhaps the most interesting period in 
the history of bookbinding was just before the close of 
the nineteenth century, when machinery was used for 
many of the different processes but while there was still 
a large amount of handwork done in the final process of 
binding. The method of that time, before the automatic 
machines robbed the art of every semblance of roman- 
ticism, was briefly as follows: 

The printed sheets were folded together and made up 
into volumes which were compressed by passing through 
rollers placed a certain distance apart. "The volumes 
are then adjusted and clamped up in the laying- or 
cutting-press for the operation of sawing the back. Two 
or three grooves are, in this operation, sawn straight 
across the back of the volume, according to the number 
of bands on which the book is to be sewed. Into these 
grooves the bands are lodged, so that when the sewing 
of the book is complete, the bands are flush with the rest 
of the back, instead of projecting out as they did in 
olden times. A slight cut is made near each end for 
holding the ' kettle stitch/ or stitch by which the sewer 
fastens her thread each time she passes up and down. 

"The sewing is done at an apparatus called the sew- 
ing-press or frame, upon which the number of cords 
to be employed are fastened at proper distances, in 

[155] 



SCIENCE IN THE INDUSTRIAL WORLD 

accordance with the saw-marks in the back of the volume. 
The method of sewing varies according as the sewer is 
working one or two ' sheets on,' and the number of 
bands employed may be from two to six, according to 
the size of the sheet, weight of the book, etc. When 
taken out of the sewing-frame the fly leaves are pasted 
on, and, the volume being neatly squared, the back 
is covered with a coating of thin glue ; it is then laid on 
a board and allowed gradually to dry. When the glue 
is quite dry the back is rounded by beating with a ham- 
mer, and subsequently the volume is placed between two 
feather-edged boards, above which the back projects 
slightly. These are then placed together in a lying- 
press, for the backing process, that is, the back of the 
book is well beaten until it projects a little over each 
side of the beveled board, so as to form a groove or 
place for the millboard covers to lie in. 

"The book is now ready for boarding. The boards 
were formerly, as the name indicates, really of wood, 
but now of millboards of various thicknesses, accord- 
ing to the size of the book. They are cut a little larger 
than the book itself, and are attached by the ends of the 
bands, left for that purpose, being passed through holes 
in the sides of the boards. The ends of the slips or bands 
are then frayed out, pasted down, and hammered flat 
and smooth. 

a The volume is next placed between pressing-boards, 
and put with others into the standing-press, where it is 
submitted to a powerful pressure for several hours. 
Thereafter it is again fastened into a lying-press for 
cutting or plowing the edges with a knife-edged instru- 

[156] 



PRINTING AND MAKING OF BOOKS 

ment called the plow. The object of the binder in this 
operation is to make every page of uniform size, present- 
ing a smooth and equal 'head/ 'tail,' and 'fore-edge.' 
The binder is careful to leave as broad a margin as 
practicable; but the size of the smallest sheet is the 
real gage of the whole book. The head is first cut, 
next the tail, and before the face is cut it is necessary 
to have the back flattened by passing 'tringles' through 
between the cords and the boards. After the face has 
been plowed the back springs back into its rounded 
form, and thus the face presents the appearance of 
having been cut in the round." 

This is the way in which most of the books on the 
market were bound until about 1890. Then improve- 
ments and inventions of bookbinding machinery began 
crowding out the slower hand-processes, just as the new 
type-setting machines and improved presses were crowd- 
ing out the older methods in the printer's domain, until 
it is almost literally true that as books are bound at 
present in the large binderies, "the binder throws in 
the material and the machines do the rest." Hand- 
stitching is obsolete, the modern stitching-machines in 
use being able to stitch books or pamphlets, of almost 
any thickness, either with cord or wire, as the binder 
may desire. Instead of a number of hand operators for 
performing the various tasks in the preparation of maga- 
zines — for example, gathering, collating, selecting covers, 
and stitching — as of old, a single machine now takes 
the sheets from the feeders, folds, gathers, collates, covers, 
and wire-stitches copies of magazines and pamphlets, 
delivering them ready for distribution. 

[157] 



SCIENCE IN THE INDUSTRIAL WORLD 

A steam rounding and backing machine has come 
into use which increases the capacity of the binder 
tenfold. Binderies with a former capacity of five 
hundred volumes a day now produce five or six thousand 
by using machines of this type. The new cover-making 
machine feeds itself from a roll of cloth which it cuts 
into pieces of the proper size as it goes along. It pastes 
these on the boards, fastens edges, smooths backs and 
sides, and drops the finished cover into a receptacle 
automatically, doing in seconds what formerly took 
several minutes to perform. Another interesting 
machine covers paper books and magazines at the rate of 
over twenty thousand a day. 

Of course leather-covered books cannot be bound by 
machinery in the same manner as cloth-covered ones; 
but even the processes involved in leather bindings are 
now mostly done by machinery. And it is almost cer- 
tain that within a short time leather books as well as all 
other kinds will be bound automatically by machinery, 
with a corresponding cheapening of price-, since, as has 
been pointed out, the binding is the most expensive 
part of book manufacture. 



[158] 



VIII 

THE MANUFACTURE OF PAPER 

DESPITE the revolutionary changes that have 
taken place in paper manufacture in recent 
years, whereby great steam-propelled machines 
produce all but the very finest grades of paper at an enor- 
mous rate, it still remains true that Western makers are 
unable to equal those of the Orient in the production of 
certain papers. The finest papers of China and Japan 
cannot be duplicated by Western manufacturers. 
"Why should they equal us?" asks the Celestial paper- 
maker, " since they are so new to the business. They 
have known the art for only a scant millennium, while 
we have been making paper for more than twice that 
length of time." 

It is probable that surrounding conditions, rather than 
the matter of longer experience, account for this ad- 
vantage of the Oriental paper-makers, although there 
is no denying them the claim that the art was old in the 
East before the West became familiar with it. Indeed, 
the West had never heard of such a substance as paper 
until a lucky fighting Arab in the eighth century of our 
era invaded Chinese territories. 

The Arab was not slow in making known his discovery 
of this valuable substance for book-making. His nation 
at that time was just becoming a nation of scribes as well 

[i59 i 



SCIENCE IN THE INDUSTRIAL WORLD 

as of fighters; and how better could one of the Faithful 
serve his master the Prophet than by introducing a sub- 
stance which would facilitate the promulgation of the 
true faith? His opinion was shared by the rest of his 
nation, and within a few years after this first discovery, 
paper-making was known all over the Moslem empire. 
The city of Damascus became the source of most of the 
paper in Christendom, and for this reason the substance 
was known as charta Damascena for many years. 

For a long time the Moors in Spain were the paper 
manufacturers for all Europe ; but after they were driven 
out by the Christians, their industry fell into the hands 
of the Spaniards. But the new proprietors were unskil- 
ful, and were slow in learning the art, so that the product 
of Moorish mills, once so famous for its quality, never 
again equaled its former standard. 

MATERIALS FOR PAPER-MAKING 

Most of the early papers were made from cotton pulp ; 
linen and other fibrous substances did not come into use 
until several centuries later. Nor is there any definite 
record of just when the transition from one substance 
to the other took place. Our most reliable source of in- 
formation at the present time is found in the specimens 
of paper themselves. These, when examined microscop- 
ically, show that wool was at one time a favorite sub- 
stance for paper-making for certain purposes, but was 
usually mixed with other substances. Pure linen paper 
does not seem to have been manufactured until early in 
the fourteenth century; and cotton paper was used for 

[160] 



THE MANUFACTURE OF PAPER 

several centuries before this, even for official documents, 
although parchment was the more common substance 
for this purpose. 

Had man been able to take advantage of Nature's 
hints more readily, he might have been a paper-maker 
many centuries before he was. For Nature sometimes 
makes a paper from a pulp in a manner almost identical 
with the simpler process now employed by man. Man 
makes paper by beating fibers into a pulp, soaking, and 
then drying them. Nature does the same thing with the 
water-plant known as the " conferna." This plant, grow- 
ing in long filaments at the bottom of pools, is disinte- 
grated by the action of the water, rising to the surface 
as a pulpy scum. The winds and waves and currents 
churn this about until, mixed into a true pulp, it finally 
washes ashore and dries as a veritable sheet of paper. 
It is quite possible that the first paper-makers of the 
Flowery Kingdom took their cue to the discovery of 
paper-making from this hint of Nature ; but if so they 
were more observing and receptive than their occiden- 
tal neighbors. 

Paper-making seems to have been introduced into 
France just at the close of the twelfth century, and as 
the successors to the Moorish paper-makers in Spain 
were making a mess of their work at that time, France 
became at once the center of manufacture for fine 
papers, with Holland as a good second. Indeed, these 
two countries held a monopoly of the fine-paper manu- 
facture for at least two centuries. Then England en- 
tered the field of competition, and soon became a worthy 
rival of the other two countries. 
vol. vm.— ii [ 161 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

MAKING PAPER BY HAND 

The early process of paper-making, which is all but 
obsolete at the present time, was slow, arduous, and 
expensive. First of all was the difficulty of getting the 
material, rags, for making the paper, as new cloth was 
obviously too expensive, and as a sufficient quantity of 
rags from any limited locality was usually difficult to 
obtain. When obtained in sufficient quantities, however, 
these rags were moistened well, and piled in heaps in 
some warm, damp place such as a cellar, and left to 
decay for twenty days or more. By the end of this time 
the perishable portion would have fermented and de- 
cayed, leaving only the fibrin, or long elastic filaments. 
These were separated from the perishable portions by 
boiling, and finally beaten to a smooth pulp by mallets. 

With the earlier paper-makers the color of the rags 
determined the color of the paper, as the chemical 
process of decoloring was then unknown. White paper, 
therefore, was very expensive, as white rags were not 
common. But later the process of using such chemicals 
as lye, lime, chlorine, etc., was discovered, and the price 
of white paper materially lessened. 

When the beaten fibers had been separated from all 
foreign substances, the mass was placed in a vat and the 
proper amount of water added to form a pasty pulp. 
To make a sheet of paper from this the operator used a 
mold made of a fine-wire screen, or cloth, which was 
stretched over a light frame. Above this frame and 
corresponding to it in shape and size, was another 
called a "deckel." In using these frames the operator 

[162] 



THE MANUFACTURE OF PAPER 

dipped the mold into the pulp, filling it even with the 
top of the deckel. This determined the thickness of 
the sheet of paper, the depth at which the mold was 
dipped determining the amount of pulp taken up, and 
consequently the thickness of the sheet. The water was 
then drained off through the wire or cloth of the mold 
by constant agitation, leaving the pulp as a spongy, 
soggy blanket. 

The " watermark," or the distinguishing characteris- 
tic of most papers, was made by designs in the arrange- 
ment of the wires themselves in the molds. When the 
wire was woven like cloth a "wove" paper was made; 
when the larger wires crossed the smaller ones at 
definite intervals, a "laid" paper was the result; and 
these names are still in use for machine-made papers. 
Of course there was no limitation to the number of de- 
signs that might be used for watermarks, and these 
came into use at a very early date, and have proved 
valuable means of identification in hundreds of instances. 

When the water had drained from the mold, leaving 
the blanket of pulp of sufficient tenacity so that it could 
be removed, it was taken from the mold and laid upon 
a sheet of felt. Other layers of pulp were placed above 
it, alternating with sheets of felt, until a "post," several 
quires in thickness, had been made. This was subjected 
to pressure until most of the water was removed, when 
the sheets of paper were taken out and hung over ropes 
or poles to dry. When dry this paper was very porous, 
being more like blotting-paper. To overcome this, the 
sheets were dipped in solutions made from boots, horns, 
hides, parchment clippings, etc., which filled the pores 

[163] 



SCIENCE IN THE INDUSTRIAL WORLD 

and made the paper non-absorbent. This was known as 
"sizing" and the solution used was called the "size." 
The paper so treated was then dried, and if an espe- 
cially smooth surface were required, was rolled between 
metal rollers. 

This process of making paper is all but obsolete at 
the present time, although a few hand-paper mills are 
still in existence. English banknotes are still printed 
on hand-made paper; but the American "greenback" 
is made by machinery. The essentials of the processes 
of hand-making and machine-making, however, are 
practically identical, the difference being largely one of 
method of application. Working under the old method, 
it took three men a day to mold and finish four thousand 
small sheets of paper, the process from start to finish 
requiring about three months. By modern methods, 
as we shall see, a forest tree, standing in its full vigor 
to-day, can be marketed as paper to-morrow. 

MODERN RAG-PAPER 

The discovery that wood pulp could be utilized for 
the manufacture of paper had a revolutionary effect 
upon paper-making machinery and paper-making meth- 
ods — for certain kinds of paper. But no means have 
been found, as yet, to produce the finer grades of paper 
from wood pulp, or from anything else, saye the time- 
honored but plebeian rag. Indeed the rag industry is 
almost as important to-day — perhaps quite as important 
— as it was when rags were the only substance used 
for paper-making. Thus we have the curious paradox 

[i6 4 ] 



' THE MANUFACTURE OF PAPER 

of the stately forest monarch used only for the making 
of plebeian papers, while the despised rag eventually 
carries the watermark of royal stationery. 

The rags used in the paper factories are literally col- 
lected from all over the world, and practically without 
any regard to condition. They arrive at the paper- 
mills in steam-compressed bales, frequently reeking 
with disease-bearing odors. The bales are sent at once 
to the machines called " openers," which tear them 
open and then pass them on to the " thrashers," which 
are huge cylindrical receptacles, revolving rapidly, sup- 
plied with long wooden arms or beaters. Here the rags 
are pounded and thrashed about, the dust and, in part, 
the odors, being carried off by suction air-tubes. Later 
they are sent to the sorting room where they are sorted 
as to size and condition, and all buttons, hooks and eyes, 
and ornaments or foreign substances removed. Here, 
also, machines with scythe-like blades, called " shred- 
ders," mangle and shred the larger pieces of cloth. 

In the ordinary paper factory the work in this room 
is most unwholesome as well as disagreeable. In fac- 
tories where only the highest grade of paper is made, 
however, this is not the case. For in such factories only 
the cleanest rags are used, and frequently only new rags, 
such as come from the clippings of shirt factories, and 
high-class tailoring and dressmaking establishments. 
Yet despite the fact that the subsequent treatment of all 
rags with steam, hot water, and chemicals renders them 
quite as "aseptic" as the new rags, most persons will 
find some satisfaction in the thought that the best papers 
on their desks are the remnants of new, rather than old, 

[165] 



SCIENCE IN THE INDUSTRIAL WORLD 

garments. It is also reassuring to know that "green- 
backs'' are made from new rags. 

After the rags leave the shredding room they are sent 
to the "cutters/' where they are still further cut and 
chopped to pieces. Here also the search for buttons and 
other foreign bodies is continued, large magnets being 
used sometimes for extracting metal buttons and other 
bits of iron or steel that may have escaped detection in 
the other sorting processes. The rags then pass on to a 
machine called a "devil," or "whipper," which is a 
hollow cone with spikes projecting within, where they 
are dashed about, and still more dust and dirt extracted, 
passing on finally to the "duster" for the final cleaning. 
This duster is a whirling conical sieve, with air blasts 
and screens, which remove the last vestiges of dirt and 
dust particles. 

Obviously all the foregoing manipulations of the rags 
are simply cleaning processes, and really have nothing 
to do with paper-making proper. But with the next 
step — the introduction of the rags into the "digesters" 
— begins the real process of turning cloth fibers into 
paper. The machines in which this process begins 
are huge revolving boilers, frequently eight or ten feet 
in diameter and twenty feet high, with a capacity for 
five thousand tons of rags. These digesters contain a 
solution of lime and soda, heated with live steam, and 
here the rags are boiled under forty or fifty pounds' 
steam-pressure from twelve to fourteen hours. 

By this time the fibers are loosened, as well as the 
dirt and colors, the contents of the boiler becoming a 
dark mushy-looking mass, that gives little promise of 

[166] 



THE MANUFACTURE OF PAPER 

snow-white paper. This is because the foreign sub- 
stances that have been loosened have not as yet been 
separated, this task falling to great tubs known as 
"Hollanders," after the country in which they were 
invented a little over a century and a half ago. 

The " Hollander' , is oval-shaped, usually about 
twenty feet long, nine feet wide, and three feet high. 
In these tubs are iron rolls covered with knives which 
revolve over a set of fixed knives below. When the rags 
are thrown in and the machinery started, a continuous 
stream of water is made to circulate about the tub. 
This carries the rags beneath the iron rolls and knives, 
which pull the mass to pieces and separate the fibers, 
which are thrown upon wire cloth where the water is 
drained off, taking with it the coloring matter, the 
rags becoming gradually whiter and whiter as the wash- 
ing process proceeds. Bleaching material is then added, 
the rags becoming perfectly white in four or five hours. 
When this stage is reached the water is drained off, 
and the mass of white fibers is thrown into drainers 
until most of the water is removed, leaving a tough mass 
having the appearance of matted cotton. 

When thoroughly drained, the mass of fibers is 
placed in the " beaters." These are machines with rolls 
and knives not unlike those in the "Hollanders" 
which draw out the fibers and separate them, and beat 
them into the paper pulp proper. If specially fine white 
paper is to be made, bluing is added to the mass at this 
stage, just as laundrymen use it for whitening linen. 

The discovery of the use of bluing was the result of an 
accident some two centuries ago. The wife of an 

[167] 



SCIENCE IN THE INDUSTRIAL WORLD 

English paper-maker named Buttonshaw, while watch- 
ing a tub of pulp, accidentally spilled the contents of a 
bluing bag into the mass. Restraining her first impulse 
to call her husband, she decided to await the result 
before confessing. To her surprise, and to the aston- 
ishment of her spouse, the batch of paper coming from 
the tub containing the bluing was the whitest, finest 
paper ever seen; and brought an unusually high price 
in the London market. His customers demanded more 
paper of the same kind, but the puzzled paper-manu- 
facturer was unable to meet the demand until his con- 
trite wife confessed. She was rewarded with a new 
bright-red cloak, and from that time London was 
furnished with the finest white paper ever brought to 
market. 

But bluing is not the only substance added to the mass 
of the pulp in the beater. Here sizing and body-color- 
ing are added, and adulterations, also, if such are to be 
used. It is here that " loading " is done — that is, clay, 
or cheap, heavy fibers are added to make a cheap 
and opaque paper. Such a paper takes the cuts for 
illustrations well, but is weak and easily torn. 

At this stage the pulp is an opaque mixture, of about 
the consistency of milk, and having very much the same 
appearance. It is, indeed, " liquid paper/' for it is 
simply a mixture of paper fibers and water; and when 
the water is drained off the paper is left behind. But, 
as we have seen in the hand-process just described, 
this separation of fibers and water is a complicated 
process. Here the old hand-mold, on which one sheet 
of paper at a time was scooped out of the vat, is replaced 

[168] 



THE MANUFACTURE OF PAPER 

by an endless wire cloth, upon which the paper can be 
made in rolls many miles long instead. The pulp is run 
up on this moving wire cloth in a layer of a certain depth, 
according to the thickness of the paper being made, 
the water draining through the meshes as it moves along, 
leaving a blanket-like layer of white pulp behind. This 
passes first under the "dandy roll," as it is called — a 
wire-cloth roll on which is woven the watermarks, de- 
signs, names, etc., which are to be distinguishing charac- 
teristics of the paper when completed. The impressions 
from this dandy roll remain more transparent than the 
rest of the paper, as can be seen by holding any sheet 
of watermarked paper to the light. 

By the time the damp blanket of paper has passed 
the dandy roll it has acquired sufficient body so that 
it can be passed between two rolls covered with felt, 
which compress it slightly, pass it on to a belt of moist 
felt, which carries it to two metal rolls called the "press 
rolls." These compress it still more, send it along 
other belts and through still other rolls until it has ac- 
quired enough tensile strength to sustain its own 
weight — can "travel alone," as the paper-men say. 
It is then ready for its journey through the drying cylin- 
ders — from a dozen to fifty of them — great, steam- 
heated steel rolls, three or four feet in diameter, over 
and under which the web of paper travels until it is 
perfectly dry. 

In this journey it acquires its full tensile strength, 
which contrasts remarkably with the delicate blanket 
of fibers that left the pulp-vat a moment before with 
scarcely more cohesive quality than mud. It still is, 

[i6 9 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

and it will always remain, a delicate substance, inas- 
much as it may be torn easily between the fingers when 
held in certain positions, but it has most amazing 
strength when even tension is applied. " In evidence 
of this," says Butler, "may be cited an instance that 
seems almost beyond belief. Through some curious 
mishap a web of heavy paper, in fact, bristol-board, 
which had been thoroughly formed, was suddenly 
superheated and then cooled while still on the driers. 
This was caused by a difference in temperature of the 
driers, and resulted in the sudden contraction of the 
web of bristol; the strain on the machine was so great 
that not only were the driving-cogs broken on two of the 
driers around which the paper was passing at the mo- 
ment, but the driers themselves were actually lifted out of 
place, showing a resisting power in the paper of at least 
several tons." 

When the paper comes from the driers it may be 
regarded as finished for certain purposes; but if it is 
to be a smooth-surface paper there still remains the 
process of " calendering.' ' The "calender" is an up- 
right set of rolls, steam-heated, through which the 
paper is whirled at the same speed at which it passes 
through the other cylinders. In fact the entire process 
is a continuous one, the paper traveling at a uniform 
speed from the time it leaves the pulp-vat until it 
emerges from the last cylinder as finished paper. This 
speed varies, of course, with different machines and with 
the different kinds of paper, but a speed of from four to 
five hundred feet a minute is not uncommon — the trot- 
ting-gait of the average coach-horse. 

[170] 




MANUFACTURE OF PAPER 



Showing the series of heated rollers over which the film of paper-making material is passed. 
The plastic mass of pulp entering at one end of the apparatus is transformed into paper and 
emerges as a finished product at the other end. The rolls of paper shown here are ready for 
the printing-press. 



THE MANUFACTURE OF PAPER 

In most of the good grades of paper, such as ordinary 
writing paper, the sizing is done, as we have seen, by 
adding the sizing matter to the pulp. With some of 
the finer grades of paper, however, the sizing is done 
after the sheet of paper is formed, by passing it over 
and under rollers through a vat containing sizing made 
from horn, hide clippings, or some similar substance. 

When a very hard, smooth surface of paper is wanted, 
there is an additional calendreing process besides the 
first one just referred to, known as super-calendering. 
The machine for doing this is a stack of rolls, a steel roll 
alternating with one of solidified paper or cotton, the 
stack containing from seven to fifteen of these rolls. 
In passing through these the paper acquires a hard, 
glossy finish. Considerable electricity is generated by 
the action of the calender rolls; so much so, indeed, 
that if not disposed of in some manner, it would inter- 
fere seriously with the working of the machine, causing 
the paper to stick, and gathering all manner of particles 
of dust and bits of dirt from the surrounding air and 
floors. To prevent this, ground-wires are usually laid 
to carry off the current. 

PAPER FROM WOOD PULP 

Until the middle of the nineteenth century there was 
very little change in the process of paper-making and 
in the kind of material used. But about this time print- 
ing-machinery began to make great changes and strides 
of progress, and the demand for cheap paper became 
imperative. The supply of rags could not meet the 

[171] 



SCIENCE IN THE INDUSTRIAL WORLD 

demand, and even if this were possible their price was 
prohibitive for ordinary papers. Substitutes were 
eagerly sought, therefore, and presently it was dis- 
covered that the fiber of certain kinds of woods, spruce 
and poplar in particular, was admirably adapted to 
making the coarser grades of paper. It was shown, in- 
deed, that any but the very finest grades of paper could 
be produced from these fibers, particularly if " flavored' ' 
with a dash of the finer rag pulp. The result of this 
discovery was completely revolutionary in the paper 
industry; the sites for some of the great paper-making 
establishments, instead of being in the centers of popu- 
lation as formerly, were now removed to the wildernesses 
of the great spruce forests, where the material for 
making the pulp was at most only a few rods away. 

For some time after the discovery that wood pulp 
could be used for paper-making, there was great diffi- 
culty in preparing the fibers economically. Machines for 
sawing and chopping the wood were tried, but they were 
not satisfactory; and when treated chemically the fibers 
in the wood resisted the action to such a degree that a 
great amount of time was required. Finally it was 
discovered in Germany that by grinding the wood with 
an ordinary grindstone, the fibers could be separated and 
turned into pulp rapidly and cheaply. It was this dis- 
covery that gave the great impetus to the wood-pulp 
industry; and it was this, perhaps more than any other 
single thing, that made possible the " penny newspaper. " 

It should not be understood, however, that only a news- 
paper quality of paper is made from wood pulp. All 
wrapping papers, most book papers, and even some 

[172] 



THE MANUFACTURE OF PAPER 

of the good grades of writing-papers are now made 
from it. And it is probably only a question of time 
until some process will be discovered whereby the pulp 
of wood will be made to take the place of rag pulp, 
revolutionizing the prices of the finer grades of paper. 

Even at the present time there are several methods 
of preparing the wood pulp in use besides that of grind- 
ing. The grinding process is the cheapest and most 
popular, but also the product is of the poorest quality, 
and the paper made from it is relatively weak. The 
several chemical processes in use produce a longer and 
better quality of fiber, and it is from some of these, 
rather than from the mechanical grinding process, that 
fine grades of paper may finally be made. Of these 
processes probably the " sulphite fiber process" is the 
most important at present. 

"In this process the wood after being barked is cut 
into small chips, which are dissolved by boiling or cook- 
ing with sulphurous acid in large boiling-tanks or di- 
gesters. The product, after being washed and other- 
wise prepared for use, has a much longer fiber than a 
mechanically prepared pulp, and is used to give strength 
to papers in which that quality is required. News-, 
common wrapping papers, and some other grades 
consist chiefly of ground wood with twenty to twenty- 
five per cent, of this chemically prepared sulphite added 
to hold them together. Other grades, such as strong 
wrapping papers, are made entirely from sulphite 
fiber. 

"This process is of American invention and was first 
used in 1867. Its early development was slow, owing 

[173] 



SCIENCE IN THE INDUSTRIAL WORLD 

to the difficulty of procuring the necessary apparatus. 
The strong chemicals employed penetrated the linings 
of the digestors as then constructed, eating into their 
shells and rapidly spoiling them for use; and until 
recently no species of lining has been found to resist 
the attacks of the acid and keep the digestors whole. 
Within a few years, however, linings have been in- 
vented which secure this end, and the sulphite process 
is now established as the leading method of securing 
chemical pulp. 

" Soda fiber is ordinarily made from woods softer than 
spruce, chiefly poplar, and is a softer, mellower fiber, 
without much strength. It is used as a soft stock 
in book, and to some extent in writing-papers. Its 
preparation is similar to that of sulphite, except that 
in place of sulphurous acid a solution of caustic soda 
is used in the digestors. The process is older than 
either of the two just mentioned, having been intro- 
duced into this country from England in 1854. It 
came into extended use earlier than the sulphite fiber, 
but owing to the greater cheapness of the sulphite 
process in producing a strong cellulose fiber from 
spruce, the use of the latter has increased more rapidly 
than that of soda. 

"The merchantable shape of these fibers differs some- 
what. Ground wood is ordinarily sold in folded sheets 
only partially dry, and is, therefore, under common con- 
ditions only suitable for use near the locality of its 
manufacture, its weight being so increased by the water 
as to preclude the profitable transportation of such a 
low-priced product, on account of the freight on this 

[i74] 




PULP-GRIXI ING MACHINERY 

The sticks of wood are held "side on" by hydraulic pressure against a rapidly 
revolving grindstone. In this way the wood-fibers are reduced to pulp, from which 
paper is made. 



THE MANUFACTURE OF PAPER 

extra weight. Sulphite is either sold in similar shape, 
first having had a portion of the water removed by 
pressure, or else dried by steam in rolls like paper. 
Soda fiber is ordinarily so sold, though sometimes in a 
partially wet state like sulphite." 2 

The process of making paper after the pulp is ob- 
tained from the grindstones, or from the chemical vats, 
is practically identical with the process used for rags. 
This is true also of the treatment of the other substances 
that are used for paper-making, such as flax, manila, 
jute, hemp, straw, and old paper. 

Reference was made a moment ago to the kind of 
paper used by the government in the manufacture of 
banknotes, or " greenbacks," and it was stated that 
only new rags are used in their manufacture — the rem- 
nants from the establishments making linen goods. 
There is another peculiarity in this banknote paper 
with which most people are familiar, and which is a 
government monopoly, inasmuch as it is unlawful for 
any person to manufacture such paper. The peculiarity 
in question is the fact that this paper contains a large 
number of tiny silk-thread clippings, of various colors, 
and from a quarter to half an inch long. These may 
be seen in any new or clean bill by holding it to the 
light, and are placed there for the purpose of preventing 
counterfeiting. 

These silk threads are inserted in the paper just 
after it leaves the pulp vat and is still a plastic blanket on 
the "wire" of the machine on its way to the cylinders. 
Just above the "wire" is a little conducting-trough, 
which sprinkles water holding the silk threads in sus- 

[175] 



SCIENCE IN THE INDUSTRIAL WORLD 

pension upon the web of pulp as it passes beneath. 
These threads are fed automatically to the trough, so 
that a uniform distribution is effected. 



WATERMARKS AND SPECIAL PAPERS 

A volume of interesting stories might be written about 
watermarks, and the important part they have played 
in romance, crime, and every-day life during the last 
five or six centuries since their discovery. Tales of 
forgeries detected and criminals apprehended, innocent 
persons liberated, and guilty ones imprisoned, would 
fill many pages of that interesting book. A fair sample 
of these would be the story of a famous forgery case of 
a century ago, involving a vast amount of property, 
where the case hinged upon a certain document which 
seemed to be authentic, but which was finally detected 
as a clever forgery by the watermark. It was definitely 
proven that the watermark of the paper on which the 
document was drawn was not used until several years 
after the supposed date of the document. From this 
mute but conclusive evidence there was no appeal ; and 
no chance remained for a difference of opinion. 

But cases of this nature have been discovered so 
frequently as to be almost commonplaces in the history of 
crime. Quite as interesting are the historical features 
of some of the ancient watermarks. For the process of 
thus putting an indelible mark upon paper has been 
known since early in the fourteenth century. The very 
first of these marks was in the form of a ram's horn; 
and later it was customary to use such commonplace 

[i 7 6] 



THE MANUFACTURE OF PAPER 

objects as tea-kettles, beer mugs, jugs, etc., as water- 
marks. King Henry VIII showed his contempt for 
the Pope by using a watermark in his stationery show- 
ing a fat hog wearing a miter. ' ' Fool's cap ' ' is the name 
handed down from the time of Charles I, when a paper 
having a fool's cap and bells for a watermark was used 
in place of paper having the royal arms, in derision of 
the monarch. "Post" paper, which was watermarked 
with a post-horn, gets its name from the old paper that 
was made " letter size," convenient for folding, before the 
days of envelopes. 

At the present time only the better grades of paper are 
given watermarks, and these are usually in the form 
of the names, or designs, of the manufacturers. The 
old custom of designating the kind of paper by such 
marks has fallen into disuse. 

The development of photographic processes for re- 
producing pictures was responsible for the polished 
paper on which the now familiar half-tone is printed. 
Such cuts can be printed on almost any kind of paper 
with modern presses; but for the very best reproduc- 
tions it is necessary to use a paper having a surface 
coated with a fine clay, and polished by calendering. 
Some idea of what a difference in results is made by 
the different papers may be seen by comparing the half- 
tone cuts in newspapers with those in the higher-class 
magazines. The newspaper cuts lack the contrasts of 
white and black, being of a more nearly uniform gray 
tone. Yet they may have been printed from the same 
half-tone cuts as the magazine illustrations. The dif- 
ference in appearance is largely due to the difference 
vol. vm. — 12 [ *77 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

in the paper used, although, of course, there is also a 
difference in the care used in printing the two publica- 
tions. 

It is possible to give a high polish to any good grade 
of paper by super-calendering; and while such a 
paper resembles the surface of a " coated " paper in 
general appearance, the coated paper can be detected 
by a simple test. If the finger is moistened and rubbed 
for a moment on the surface of any coated paper, the 
clay will be loosened and adhere to the skin in a thin 
film of powder. This will not occur with any other kind 
of paper; and this test can be made with any illustrated 
magazine, the pages having the illustrations being of 
coated paper, while the text pages, particularly if there 
are several together without pictures, are very likely 
to be of plain paper. 

The clay used for making this coated paper comes 
from Cornwall, England, and is pure kaolin, or china- 
clay. This is ground to the fineness of fine flour, mixed 
with glue and spread on a body-paper, dried, and calen- 
dered. This coating-process is a special department of 
paper-making, and many large establishments, where 
coated paper is manufactured, do not make any of their 
own body-papers, but obtain them from other manu- 
facturers. 

The machinery for coating the paper is very simple. 
It consists essentially of a vat for holding the coating 
material — the "enameling solution' ' as it is called — 
some rollers for regulating its distribution, sets of brushes 
for working out lumps and still further regulating the 
distribution, and automatic carriers for taking the paper 

[i 7 8] 



THE MANUFACTURE OF PAPER 

through the drying-room before going to the calenders. 
The calenders are the same as those used in the other 
processes of paper-making. When a web of paper is 
to be coated on both sides it is started on rollers through 
the enameling solution, emerging between two rolls 
which regulate the thickness of the coating and re- 
move the surplus. Next it comes in contact with the 
brushes, arranged in sets so that the coarser brushes 
act upon it first, fine camel's-hair brushes giving it the 
finishing touches. It is then passed on to the automatic 
carriers, which take it through the drying-rooms heated 
to about 140 F. where it becomes perfectly dry before 
being sent to the calenders for the final polishing. The 
degree of polish given the paper depends upon the 
amount of pressure used on the calender rolls, and 
the number of times that the sheet is passed through 
the machine. 

This paper is somewhat similar to the glazed papers 
used for covering boxes, and for making many fancy 
articles. But in these papers wax is added to the coat- 
ing, giving it the familiar gloss. 

SPECIAL USES OF PAPER 

In recent years paper has been used for a greater 
variety of things than almost any other substance. Even 
to catalogue these would require a volume. And 
curiously enough these uses are as diversified and 
frequently as diametrically opposed to each other as 
possible. Treated in a certain manner paper may be 
used as tinder for lighting fires; or if treated by a dif- 

[i79] 



SCIENCE IN THE INDUSTRIAL WORLD 

ferent process the same fibers may be used as a compo- 
nent of fireproof substances, such as the drop-curtains 
in the theaters and the packing of engines. By proper 
manipulating it is made into soft, pliable, felt-like 
"chamois fiber, " or compressed and hardened into an 
ideal material for car wheels. In short, it can be made 
to take the place of down, or steel, or almost any other 
substance of intermediate density. 

When the manufacture of paper car wheels was 
announced a few years ago it was generally supposed 
that this was simply the experiment of some imagina- 
tive enthusiast. Few people took the announcement 
seriously. But in point of fact the paper car wheel has 
no rival for endurance and reliability. The cost of 
manufacture is its principal drawback. The process of 
making these wheels is as follows: — 

"The material used is calendered rye-straw board, 
or thick paper, and the credit of the invention belongs 
to Richard N. Allen, a locomotive engineer. The 
material is sent to the car-wheel shops in circular 
sheets measuring from twenty-two to forty inches in 
diameter, and over each of these is spread an even 
coating of flour paste. The sheets are then placed one 
above the other until a dozen are pasted together, 
when all are subjected to a hydraulic pressure of five 
hundred tons or more. After two hours' pressure, 
these twelve- sheet blocks are kept for a whole week in 
the drying-room heated to a temperature of 120 F., 
after which a number are pasted together, pressed, and 
dried for a second week; a third combining of layers is 
then made, followed by a month's drying, until there is 

[180] 



THE MANUFACTURE OF PAPER 

obtained a solid block, containing from one hundred 
and twenty to one hundred and sixty thicknesses or 
sheets of the original paper. The thickness is only 
from four and one-half to five and one-half inches, and 
in weight, density, and solidity the block resembles 
more the finest-grained, heaviest metal than it does 
the original paper product. It may be called car- wheel 
paper. To complete the wheel there are required a 
steel tire, a cast-iron hub, wrought-iron plates to pro- 
tect the paper on either side, and two circles of bolts, 
one set passing through the flange of the tire, the other 
through the flange of the hub, and both sets through the 
paper. The paper blocks are turned on a lathe, which 
also reams out the center- hole for the hub; two coats 
of paint are applied to keep out moisture ; the cast iron 
is pressed through by hydraulic pressure; the other 
parts are forced into place, and the paper center is 
forced into the steel tire by like hydraulic power; and 
there, a product of human ingenuity, is a paper car 
wheel, which never is injured by vibrations, and is safer 
and longer-lived, though costing more, than any other 
car wheel made." 

But the wheels of cars are not the only part of the 
car that is sometimes made of paper. The boards for 
interior finishings, and sometimes the seats, are made 
from what is known as " paper lumber." This paper 
lumber is made by passing ordinary straw-board through 
a vat of resin and other waterproofing at a temperature 
of about 350 F., then placing a number of these sheets 
together and subjecting them to hydraulic pressure. 
Boards so made are usually about a quarter of an inch 

[181] 



SCIENCE IN THE INDUSTRIAL WORLD 

thick, of a dark, blackish color, and may be worked with 
the saw and chisel the same as ordinary boards. They 
are only adapted to certain purposes, and are relatively 
expensive as compared with common lumber. A very 
common use of such boards is for the perforated seats 
used in waiting-rooms. 

A more useful substance, and a much more familiar 
one, is papier-mache, which has been used for various 
purposes for something like a century. Ordinarily it is 
made from waste paper, repulped and mixed with a 
strong size of glue and paste, to which chalk, clay, or 
lime is sometimes added. To make the finest papier- 
mache, strips of specially made strong paper are 
soaked in a strong size of paste and glue, molded into 
any shape required, and dried in an oven. They are 
then hardened by dipping in oil, trimmed, and japanned 
or painted, and made into one of a thousand different 
useful or ornamental articles, such as boxes, trays, 
artists' lay-figures, picture frames, and mural decora- 
tions. This substance is used also for certain kinds of 
roofings, and is a very excellent floor-covering. 

The antithesis of these hard-paper products is the 
chamois fiber, just referred to. This is made from the 
long-fibered sulphite stock of the wood-pulp factory. 
As this pulp passes through a set of special machines 
the fibers are mangled and pulled about until the 
resulting fabric is a soft, flexible, chamois-like sub- 
stance. It is impervious to air, is a poor conductor of 
heat and cold, and, as it wears fairly well, is sometimes 
used for making undergarments. 

Obviously it would be useless to attempt even the 

[182] 



THE MANUFACTURE OF PAPER 

mention of the useful articles that have become essen- 
tial to civilization and that are the products of the pulp. 
Buttons, books, boxes, houses, canoes, cars, furniture, 
pails, barrels — almost everything, indeed, that one can 
think of or imagine. The case is covered by the state- 
ment of a recent writer, who said, " Since the introduction 
of wood pulp, paper figures, either wholly or in part, in 
more diverse and numerous articles than any other one 
substance known." 



|is 3 ] 



IX 

THE REPRODUCTION OF ILLUSTRATIONS 

THERE is hardly a more striking example of 
nineteenth-century advance in the methods of 
communicating ideas than that of modern 
processes of reproducing pictures. Fifty years ago an 
energetic wood-engraver, by working long hours every 
day for a month, could produce an illustration the size 
of one of the ordinary illustrations in the Sunday news- 
paper. The same sized illustration can now be pro- 
duced, with more fidelity to nature, in an hour. And 
yet up to the time of the beginning of the last quarter 
of the nineteenth century this process of wood-engrav- 
ing was the only practical way of reproducing illustra- 
tions for such publications as books, magazines, and 
newspapers. There were other methods of reproduc- 
ing pictures, to be sure, such as etchings, lithographs, 
etc., but for the most part these cannot be used for 
ordinary newspaper or book illustrations. The wood- 
engraving was therefore the most important as it was 
the oldest form of reproducing pictures. 

Just when or where wood-engraving made its first 
appearance cannot be determined. The earliest ex- 
amples of wood-engravings now extant date from about 
the time of the invention of printing from movable 
types. It is probable, therefore, that wood-engraving, 

[i8 4 ] 



REPRODUCTION OF ILLUSTRATIONS 

at least in a crude form, antedated this period by many 
centuries, although the impetus to book-making given 
by the introduction of the printing-press undoubtedly 
stimulated the development of wood-engraving; and 
the history of the making of reasonably good wood 
blocks begins with the history of the printing-press. 

Of course, making impressions from engraved sur- 
faces must be practically as old as carving itself, dating 
back to prehistoric times, since the principle involved 
in wood-engraving is practically the same as wood- 
carving and metal-chasing, where certain portions are 
removed, leaving other portions of the wood and metal 
on a level with the surface. It must have happened 
many times, therefore, either accidentally or other- 
wise, that the wood-carver or metal-worker made 
impressions on cloth or paper from his carvings. Such 
impressions are still made by metal-engravers from time 
to time as their work progresses, and there is reason to 
believe that ancient metal-workers were familiar with 
this method of printing their work. This being the case, 
it is probable that designs of carving or chasing were 
frequently copied by means of impressions upon cloth 
or leather, which of course is a rude form of printing 
from the engraved surface. But no records have been 
preserved showing that this method was ever used ex- 
tensively in reproducing pictures. 

By the beginning of the fifteenth century wood- 
engraving had reached a comparatively high state of 
development, and from that period on, thanks to the 
printing-press, there is no difficulty in tracing the ad- 
vances made in the art. In fact the earliest types used 

Ms] 



SCIENCE IN THE INDUSTRIAL WORLD 

in printing were simply wood -engravings made by dig- 
ging out the wood about the letter, either separately 
or in words or sentences. 

A simple illustration of the way in which a crude 
woodcut may be made is to write any word written in 
the ordinary manner with pen or pencil upon a block of 
wood having a perfectly even surface. If, now, the sur- 
face of wood about the letters is dug away, leaving the 
letters standing out in relief, it is obvious that a facsimile 
impression may be taken from this primitive woodcut 
by inking the surface of the letters and pressing a piece 
of paper upon them. An impression so made will of 
course be reversed, so that in order to have the woodcut 
reproduce the word in its correct form when printed, it 
is necessary that the word be reversed in writing it upon 
the block. This simple principle holds true in all wood- 
engravings, and for that matter practically all processes 
of reproduction, ancient or modern. 

For many years a, woodcut representing a picture of 
St. Christopher and dated 1423 was considered the 
oldest woodcut in existence. It seems practically certain, 
however, that there are a few examples of even earlier 
work than this, some of them having a date as early as 
1406. In these woodcuts little attempt is made to repro- 
duce lights and shadows, the figures being represented 
mostly by simple outlines. But in the woodcuts which 
appeared in great numbers shortly after this time, 
fairly successful attempts were made to represent lights 
and shadows of various gradations by the use of finer 
or closer lines, just as in modern wood-engravings. 

It is obvious that if the surface of the block of wood 

[186] 



REPRODUCTION OF ILLUSTRATIONS 

is left untouched, it will give a perfectly black impression 
to the paper when inked. It is equally apparent that 
in portions that may be cut away from the surface of 
this block, it will show as white space on the paper. To 
produce a perfectly black spot, therefore, of any 
desired shape, the wood-engraver has but to outline this 
shape and cut away the surface of the block about it. 
Conversely, if he wishes to have the space of a certain 
shape remain perfectly white, he has but to dig out the 
surface of the wood in the desired shape. In pro- 
ducing perfectly black or white effects, therefore, there 
is little difficulty, and comparatively little skill is 
required. For intermediate tones, however, such as dark 
or light grays, the wood-engraver makes use of parallel 
or crossed lines, either wide apart or close together 
according to the tone he wishes to reproduce. It is 
obvious that if he wishes to reproduce a very dark 
surface he would leave the lines heavy and close together, 
or if he wishes to lighten these tones he would simply 
cut away more of the wood between the lines. In this 
way it is possible to represent a perfectly black surface 
gradually grading into a white one, simply by using 
parallel lines which gradually diminish in size until 
they finally disappear entirely. 

This is the general principle which lies at the founda- 
tion of all wood-engraving, and no departure is made 
from it, except in the matter of skill in application, in a 
delicate woodcut of a Timothy Cole or a Henry Wolff 
of to-day, or the unknown engraver of the picture of 
St. Christopher in 1423, although this is not apparent in 
the finished product. 

[187] 



SCIENCE IN THE INDUSTRIAL WORLD 

About the middle of the fifteenth century another 
method of wood-engraving called crible came into use. 
In this method of engraving the wood was not cut away 
in lines as in the ordinary wood-engravings, the various 
tones being obtained by punching holes in the surface of 
the block. By this method all gradations in tones were 
obtainable, the results being not unlike coarse spatter- 
work or dotting, as done in certain kinds of pen draw- 
ings. This process, while giving excellent results, was 
extremely slow and tedious, and passed out of existence 
entirely a little later, except for certain purposes for 
which it is still admirably adapted. For astronom- 
ical charts, for example, where the sky is repre- 
sented as a black background, and the stars as 
points of light of various sizes and in certain posi- 
tions, the crible method of wood-engraving gives ex- 
cellent results. 

The sixteenth-century wood-engravings were a great 
improvement over those of the preceding century, 
probably the best known being the pictures of Albrecht 
Diirer. Some of these are so skilfully engraved that 
they approach the perfection of modern engravings, 
although, of course, lacking in perspective and color- 
values which have become one of the essentials of 
modern illustration. From the time of Diirer, the im- 
provement in wood-engraving was a steady growth until, 
by the beginning of the last quarter of the nineteenth 
century, it had reached its highest perfection. Then, 
about the year 1887, photographic-process reproduc- 
tion made its appearance, and since that time wood- 
engraving has rapidly declined until, as a method of 

[188] 



REPRODUCTION OF ILLUSTRATIONS 

reproducing artistic pictures, it has practically disap- 
peared except for special purposes. 

TECHNIC OF WOOD-ENGRAVING 

In making drawings for wood-engravings the artist 
usually drew directly upon the surface of the block of 
wood that was to be engraved. The wood used ordinarily 
was boxwood, cut across the grain. To facilitate work- 
ing on this surface it was usually covered with a light 
coating of Chinese white, which enabled the draughts- 
man to see the effect of his drawing very much as it 
would appear on white paper when printed. This 
drawing was of course exactly the size that it appeared 
in print, the artist being thus greatly handicapped in a 
manner quite unknown to modern illustrators, whose 
drawings may be made any convenient size without 
regard to the size of the reproduction to be made. 

Although the wood-engraver was obliged to produce 
his effects by means of lines, it was not necessary for 
the artist to indicate each of these lines unless he chose 
to do so. He might make his drawing on the block with 
a brush or pencil, indicating the shadings as he wished 
them, but leaving it to the artistic sense of the engraver 
to determine the direction and size of the lines used in 
interpreting the various shades and tones. It is obvious 
that when the artist drew in this manner the result ob- 
tained was due largely to the skill of the engraver, a 
good engraver frequently improving the original work 
of the artist while a poor engraver might ruin the work 
of a good artist. For this reason good engraver? *vere 

[189] 



SCIENCE IN THE INDUSTRIAL WORLD 

at a premium, the best artists frequently working in 
conjunction with their engravers, or stipulating with 
publishers that only certain engravers should be allowed 
to reproduce their work. 

As a natural outcome of this position of artist and 
engraver, disputes were constantly arising between the 
two classes of men, each claiming the lion's share of 
credit for a good illustration, or placing the blame upon 
the other in case of poor work. A characteristic attitude 
of the artist toward the engraver is shown in an expres- 
sion of one of the artists illustrating for Punch in the 
early days. ' ' Here is the drawing, ' ' he remarked ; ' ' now 
see the engraver spoil it " — which, as a matter of fact, he 
frequently did. 

There was another method of drawing, however, 
whereby very little was left to the artistic skill and in- 
terpretation of the engraver. That was where the draw- 
ing was made in lines with a pen by the artist himself, 
the task of the engraver in such cases being simply to 
cut out the spaces between the lines. In this way the 
artist's work was reproduced with great fidelity, and 
the onus of the result obtained rested entirely with him. 
The engravers working upon this kind of drawings 
required relatively little skill as compared with the ones 
who determined their own lines for reproduction. 

The amount of work and time required to make even 
small wood-engravings with a comparatively coarse 
line, will be apparent to anyone by glancing at a print 
of such a block. Every line, some almost microscopic 
in size, must be cut out carefully with an engraving 
tool. Not only is this a tedious task, but one requiring 

[190] 



REPRODUCTION OF ILLUSTRATIONS 

a great amount of mechanical skill, for even the slightest 
slip of the tool could ruin an engraving, or a considerable 
portion of it, that may have taken hours or even days to 
produce. 

If only a single engraver worked upon a single large 
engraving, as he usually did in the best class of work, 
the time required to produce such a block was so great 
that for ordinary weekly, or monthly, periodicals, 
where timeliness is a determining element, its use was 
out of the question. To hasten the engraving-process, 
therefore, it was customary to cut the block into several 
smaller pieces after the artist had finished his drawing, 
turning over the pieces to a corresponding number of 
engravers, each of whom engraved the section of the 
picture assigned him. This was of course a great saving 
of time, as the blocks could be clamped together when 
finished, ready for printing, presenting the same ap- 
pearance and giving the same result as in the case of the 
single block. In such cases the individuality of the en- 
graver was, of course, lost — a most important element 
in fine engravings. 

Waiving questions of the relative artistic effects ob- 
tainable by wood-engraving as compared with modern 
photographic methods, two other elements were de- 
terminative in deciding the question of the survival of 
wood-engraving when in competition with photographic 
processes. These elements are time and cost of produc- 
tion. The time consumed is of course commensurate 
with the cost where human labor is concerned, and the 
relative time of producing a wood- engraving as com- 
pared with a photographic block may be roughly repre- 

[191] 



SCIENCE IN THE INDUSTRIAL WORLD 

sented in some such ratio as that of minutes to hours. 
This being the case, it will be readily understood that, 
from the commercial point of view, the wood-engraving 
must go out of existence. It has one advantage, aside 
from its mooted artistic superiority over certain forms 
of photographic engravings, in that it may be printed 
with reasonably good results on cheap paper and repro- 
duced an almost endless number of times without deteri- 
oration. For this reason, in cases such as illustrations 
for advertising purposes, etc., in newspapers, which are 
to be repeated day after day in millions of impressions, 
the wood-engraving is still used, the elements of time 
and cost of production being unimportant. On the other 
hand such engravings have little advantage for such 
purposes over the modern "zinc etching," or "zinco," 
as it is vulgarly called, to be referred to more fully in a 
moment, which may be produced so much more quickly 
and inexpensively. 

COPPER- AND STEEL-PLATE ENGRAVINGS 

Shortly after the time of the introduction of the wood- 
engraving, and possibly at a much earlier period in its 
crudest form, reproduction of pictures made from 
engraved metal plates came into use. The method of 
engraving such plates and of printing them was exactly 
the converse of the process of wood-engraving, although 
this is not shown in the finished prints. In the wood- 
engraving the part of the surface designed to make the 
impressions of the ink upon the paper is the part left by 
the engraver, the hollowed-out part between the lines not 

[192] 



REPRODUCTION OF ILLUSTRATIONS 

being touched by the ink, and therefore represented by 
the white paper in the reproduction. With a copper- 
or steel-plate engraving, however, the hollowed-out 
lines of the engraving represent the black lines in the 
finished picture, those hollowed spaces taking the ink 
from the roller or pad and conveying it to the paper, 
the surface of the plate not taking the ink. A good 
example of this kind of engraving is the plate of the 
ordinary calling, or business card, as anyone may 
observe by inspecting his plate. 

This kind of engraving is supposed to have been first 
introduced by a goldsmith of Florence some time in the 
fifteenth century, although, as noticed before, it was 
probably used for certain purposes much earlier. It 
was customary for these metal-workers to bring out the 
sharp outlines and effects of their carving upon the gold 
by filling the spaces made by the engraving tools with a 
kind of black enamel. In this way the beautiful de- 
signs cut in the metal were sharply outlined by contrast. 
These engravers, wishing to take impressions of their 
work from time to time, were in the habit of covering the 
surface of the engraved metal with some kind of coloring 
matter, wiping the excess from the surface, and making 
their impressions by pressing paper over the surface so 
treated. In this manner it was discovered that designs 
of the greatest delicacy could be transferred to paper; 
and from these tentative attempts the process of repro- 
duction by copper and steel plates finally developed. 

Copper as the softer and more easily workable metal 
was the one generally employed, but the durability 
of the steel plate once it was finished made it prefer- 
vol. vin— 13 [ 193 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

able for certain purposes. The popularity of this kind 
of engraving was greatly increased by the interest taken 
in the process by some of the great painters, particu- 
larly those of the fifteenth and sixteenth centuries. In 
this process such artists as Diirer, Rubens, and Raphael 
saw the possibility of multiplying and distributing a 
great number of copies of their paintings and drawings, 
and giving them a wide circulation all over the world. 
It also offered a means of preserving reasonably accurate 
representations of their work which might otherwise 
be accidentally destroyed and lost, or, being sold and 
removed to some distant city, would be lost to the artist 
except as a vague memory. For this and other reasons 
all the artists of that period encouraged the line en- 
graver, some of them being skilled in the actual technic 
of the engraving-process itself. 

Most of the great painters, however, confined their 
efforts to directing the work of the engraver rather than 
to undertaking the tedious task of cutting the metals 
themselves. For this work, like the work of the wood- 
engraver, was done with a pointed chisel, or sharp tool, 
called a "burin," and each line to be reproduced repre- 
sented a corresponding gouging-out of metal with this 
implement by manual labor. 

In the nineteenth century, steel-engraving for repro- 
ducing pictures very generally supplanted copper-en- 
graving; but both of these methods of reproducing 
have gone out of use except in certain cases where, 
in special editions of books or pictures, the publisher 
finds it advantageous to revive this practically obsolete 
form of illustration. 

[ 194 ] 



REPRODUCTION OF ILLUSTRATIONS 



ETCHING 

A form of engraving which became popular perhaps 
a century later than the line engraving and which is 
still popular, particularly among artists, is the etching. 
In this process, as in the copper plate, the lines which 
are to be reproduced are cut into the surface of the 
metal. But the actual cutting is not done mechanically 
with a tool but is accomplished by a chemical process, 
after such lines have been indicated on the waxed surface 
of the plate. 

In preparing such an engraving the etcher covers 
the surface of the copper plate with a specially prepared 
compound of wax smeared over the surface in a thin 
layer. This wax is not affected by the actions of acids, 
whereas the copper may be quickly eaten away by them, 
or " etched, " to any desired depth. By using a pointed 
needle, therefore, which will scratch away and remove 
any portion of the thin layer of wax that it touches, 
surfaces presenting corresponding lines of copper may 
be exposed, which will be eaten out of the surface of the 
copper, as pressed by the needle in the wax. In this 
manner the mechanical effort of cutting out lines is 
entirely done away with, and the artist is free to make 
his drawing upon the waxed surface of the copper with a 
pointed instrument which may be moved about with 
the greatest freedom. It is possible, also, to correct errors 
when made before the acid is applied, by resmearing the 
surface with wax and making over again the drawing 
at this point. 

[ 195 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

The advantage of the etching lies in the fact that, 
owing to the minuteness and freedom of the lines, it is 
possible to produce most artistic effects. These qualities 
especially appeal to the painter, and many of the great 
painters have also been great etchers. Of the older 
masters, Rembrandt and Van Dyck were famous for 
their etchings ; and in recent times such men as Whistler 
and Seymour Haden have been great exponents of 
this kind of engraving. 

MEZZOTINT 

There is another form of metal-engraving, called 
mezzotint, which was invented in 1643 by Van Siegen, 
a Dutchman, though erroneously ascribed to his pupil, 
Prince Rupert. This is a mechanical process like the 
copper-plate engraving rather than the etching, but in 
which the line, made by a pointed instrument like the 
burin, is not employed, the plate being prepared and 
worked upon in a peculiar manner. To prepare a plate 
for mezzotint work a peculiar instrument is used, this 
instrument having the edge ground into the segment of a 
circle, and so engraved as to present something like a hun- 
dred minute teeth. When this ' ' cradle ' ' is pressed upon 
the surface of copper and rocked back and forth, a great 
number of minute dents will be made in the copper, 
each dent, of course, raising a corresponding burr. 
In preparing such a mezzotint plate the surface of the 
copper must be worked over something like a hun- 
dred times, the cradle being worked in different 
directions. 

[196] 



REPRODUCTION OF ILLUSTRATIONS 

When finished, such a plate presents a surface which, 
if inked, presents an absolutely black tone. For pro- 
ducing the desired effect of outlines, and lights and 
shadows, upon such a plate, the engraver scrapes away 
with a point, or scraper, such portions as he wishes for 
forming the outlines, controlling the tone by light or 
heavy scraping as the case requires. This process is 
of course a most tedious one, but the results obtained 
from a good mezzotint more nearly resemble effects in 
nature than any other form of reproducing before the 
introduction of photography. Prints from the mezzo- 
tint plate had to be very carefully made, and only a 
comparatively small number could be obtained from a 
plate, the pressure of the paper soon wearing it out. 

THE INVENTION OF LITHOGRAPHY 

The process of printing illustrations, letters, or dia- 
grams by lithography is one in which stone is used in 
place of wood or metal, as in the case of wood-engraving 
and line engraving. The process of preparing the stone, 
so that certain surfaces will print while others will not, 
is done in several ways. In a general way, portions of 
the stone which are to come in contact with the paper 
are raised above the surrounding surface by treating 
their surfaces with some substance not acted upon by an 
acid, and then biting away the surrounding stone to the 
desired depth. Another method of accomplishing this 
same thing, however, is by treating the surfaces of the 
printing portion with some substance that will absorb 
printing-ink, while the surrounding stone is kept 

[i97] 



SCIENCE IN THE INDUSTRIAL WORLD 

moist with a substance that does not absorb the ink. 
In this way the antagonistic qualities of grease and 
water are made to take the place of the raised surfaces 
in printing. Still another method, practically the same 
in principle although somewhat different in application, 
is to blot out on the stone certain portions which are not 
to appear in the printing, leaving the exposed surfaces 
for absorbing the ink and transferring it to the paper in 
the process of printing. These apparently simple proc- 
esses are subject to endless variations and, of course, 
require a great number of complicated details in practical 
lithography. The principle involved, however, is 
practically the same in all kinds of lithography. 

This method of reproducing pictures was discovered 
near the beginning of the nineteenth century by Alois 
Senf elder, a native of Prague. Senf elder, being an 
ambitious but very poor playwright, had made various 
experiments in attempting to reproduce pictures for 
his writings in order to save the expense of wood-en- 
graving. Having occasion at one time to write some 
notes, and finding no paper at hand, he wrote these 
notes upon a slab of stone which he used in grinding his 
ink. As it happened, the ink used in this writing was of 
a composition that would resist the action of acid. A 
few days later, when about to erase this writing from 
the stone, it occurred to Senfelder to treat the surface 
with an acid to see what the effect would be. The re- 
sult was most surprising, for at the end of five minutes 
the stone had been eaten away to the depth of about 
one one-hundredth of an inch, leaving the lines of the 
pen strokes raised in relief sufficiently to receive ink 

[i 9 8] 



REPRODUCTIONS OF ILLUSTRATIONS 

from a pad or roller. Fortunately, Senfelder remem- 
bered the composition of the ink used, and recognizing 
the possibilities of this entirely novel and rapid method 
of reproduction, he began a series of experiments and 
made numerous improvements so that by the time of his 
death, in 1834, he had brought lithography to a high 
state of perfection. 

Of course this method of reproduction does not lend 
itself to illustrations in which the pictures are to be 
incorporated with type, as in the text of books and 
magazines, for the lithographic stone is necessarily 
too large. But for certain classes of work, lithography 
is still extensively employed, and since it lends itself to a 
combination with photographic processes, it seems likely 
to continue in use for some time to come. 

Only certain kinds of stone are suitable for fine 
lithographic purposes, such stone being the very hard, 
homogeneous limestone which is found mostly in Ger- 
many, although stone of inferior quality may be obtained 
in several other countries. The surface of the stone 
is prepared according to the use for which it is designed, 
sometimes being polished perfectly smooth and at other 
times roughened very slightly or in a very coarse grain. 
When thus prepared, the artist makes his drawing with 
lithographic ink or with a special pencil or crayon made 
of some substance that will resist the action of the 
acid. In this way lights and shades may be represented 
in line on the polished stone, or may be indicated as 
tones with a crayon or with a pen on the roughened stone, 
the grains of which retain small or large quantities of the 
lithographic chalk according to the pressure used. If, 

[i99] 



SCIENCE IN THE INDUSTRIAL WORLD 

for example, the artist wishes to produce a light-gray 
effect, he may do so by rubbing the crayon lightly over 
the surface of the stone, and he may intensify this shade 
to any desired degree by increasing the amount of pres- 
sure, thus depositing more of the acid-resisting sub- 
stance ; or he may produce a flat black effect by covering 
the surface of the stone with ink. 

It will be seen that in this process the lights and 
shadows are not reversed, the lithographer drawing 
and shading them in the same manner as would be done 
in an ordinary drawing, although the composition of the 
picture is reversed. One of the features of lithography 
is the remarkable results that may be obtained by its 
use in color-printing. In principle this printing with 
many colors is simple enough, but when it is con- 
sidered that for every color used a separate stone and a 
separate printing on the same piece of paper is neces- 
sary, registered so accurately that there will not be the 
slightest variation in its position as it is placed on the 
successive stones, the results shown in the finished 
color-print seem little short of marvelous. 

When a colored picture has to be duplicated by 
lithography, the lithographer first determines how 
many colors will be required to produce the desired 
effect. An outline of the picture is then made of exactly 
the right size on a stone, and the patches of color are 
carefully outlined. This stone, which is known as the 
keystone, determines the exact position of each of the 
colors as they will appear on the separate stones. Sup- 
pose the picture to be reproduced is a simple one, 
using, let us say, five colors. This will necessitate the 

[ 200] 



REPRODUCTION OF ILLUSTRATIONS 

use of five separate stones unless, as often happens, 
colors can be produced by superimposing them or by 
combining more than one color on a single stone. The 
artist will then select a color, red, let us say, noting 
from the keystone every patch of red as outlined there. 
In exactly the same positions on another stone the out- 
lines for the reds are made, of corresponding shapes, 
omitting all other parts of the picture. On a second 
stone he will treat the outline of the blues in the same 
manner, on a third stone the yellows, and so on until 
each color to be used is represented on the stone in a 
position so that if the colored inks are applied and a 
piece of paper in an exact relative position to each stone 
is successively pressed upon each of these stones, a pic- 
ture in five colors, practically duplicating the original, 
will be produced. 

Of course if each of these patches of color on a stone 
were simply outlined, leaving a perfectly flat surface for 
printing, with the remaining surface of the stone cut 
away by the acid, the result would be a perfectly flat 
mass of color for each patch so treated. As shading is 
usually desired, however, this is produced with chalk 
or pen as described a moment ago, dark patches of 
color being indicated by heavier marks and the lighter 
ones by correspondingly lighter marks. 

In recent years aluminum has been used extensively 
to take the place of lithographic stone. On this metal 
the inks can be worked well, and its lightness and 
relatively small bulk have brought it into general favor. 
In the same space occupied by a single lithographic 
stone a great number of aluminum impressions can be 

[201] 



SCIENCE IN THE INDUSTRIAL WORLD 

stored, so that the matter of storage space alone be- 
comes an important factor. 



THE INTRODUCTION OF PROCESS WORK 

In all the methods of reproducing pictures that have 
been described so far, the artistic skill of the engraver 
or lithographer has played an important part. Any 
workman to be successful in producing illustrations by 
means of any of these methods must not only have 
acquired a certain degree of perfection in mechanical 
skill, but also have considerable artistic ability. As 
a combination of these two qualities is rarely found in 
the individual who has chosen engraving as a calling, 
it followed that good reproductions of pictures which 
really interpret the work of the artist satisfactorily, 
were only produced by a limited number of high- 
priced workmen. 

On the discovery of photography by Daguerre, 
whereby chemical rather than mechanical means were 
used for reproducing representations of natural ob- 
jects with more fidelity than by any method previously 
known, attention was directed to applying this new- 
process to the reproduction of pictures. For many 
years these efforts were not successful, but about the 
beginning of the last quarter of the nineteenth century, 
it was discovered that a mixture of albumin and bi- 
chromate of potash could be hardened by exposure to 
light, this hardening varying according to the intensity 
of the light, the resulting hardened substance not 
being acted upon readily by acids. 

[ 202 ] 



REPRODUCTION OF ILLUSTRATIONS 

If, therefore, a copper or zinc plate were covered with 
a film consisting of a mixture of fish-glue, albumin, 
and bichromate of potash, and portions of it so covered 
that they were not acted upon by light, while other por- 
tions were exposed to it, it was found that by treating 
this plate chemically and then placing it in an acid bath, 
the portions exposed to the light retained their original 
surfaces while the covered portions were eaten away. 
In other words, an engraving could be made in this 
manner. It made no difference as to the size of the sur- 
faces covered or exposed to the light, a thin line being 
protected against the attack of acid by the hardened 
bichromate mixture as readily as a white blotch. If, 
for example, lines in black ink were drawn upon a 
surface of glass, and this glass placed over a sensitized 
copper plate and exposed to light, the lines would ap- 
pear as depressions in the plate when treated with 
the acid, as the ink would protect the thin film of the 
sensitized medium from the light. On the other hand, 
if this drawing upon the glass were reversed so that 
the lines made by a dry pen or point appeared as 
transparent lines, like scratches on smoked glass, such 
lines, allowing the passage of light, form hardened 
lines in the bichromate mixture, and, when the plate is 
treated with the acid, appear as raised surfaces like 
the printing-lines of a woodcut. In short, if the artist's 
drawing were scratched upon a glass covered with an 
opaque substance, an engraved reproduction of his 
drawing could be made upon zinc or copper plates by 
the process just described. 

In actual practice such a method of drawing is 

[203] 



SCIENCE IN THE INDUSTRIAL WORLD 

difficult to use and is not practical, but by making use 
of photography the same effect may be produced if the 
drawing is made in the ordinary method with pen on 
white paper. For the negative made by the camera 
reverses the lights as they appear in nature, the black 
lines on the white paper appearing on the photographic 
negative as transparent lines on a black background — 
like the scratches on the smoked glass, just referred to. 

Such a negative is then placed over a sensitized zinc 
plate and printed in the same manner as the photo- 
graphic plate. The light passing through the open- 
ings in the glass plate corresponding to the lines of the 
drawing hardens the bichromate mixture beneath. 
The zinc plate is then " rolled up" with an ink-roller 
carrying an acid-resisting ink, placed in water, and de- 
veloped. Wherever the light has penetrated the hard- 
ened bichromate mixture remains, the other portions 
being washed away. The plate is then dried and 
strengthened by a resinous powder, and after being 
slightly heated is placed in the acid bath. 

In this manner a drawing may be reproduced with 
the greatest fidelity, every pen stroke of the artist ap- 
pearing exactly as it was made in the original. Here 
was a process that was at once rapid, cheap, and 
absolutely accurate, and this is the method in use to- 
day for reproducing pen drawings as used in news- 
papers and other publications. 

This discovery was the first great blow to the wood- 
engraver, who could no longer hope to compete with so 
simple and rapid a process which, in the end, interpreted 
the work of the artist fully as well, if not better, than 

[204] 



REPRODUCTION OF ILLUSTRATIONS 

the woodcut. And most of the artists themselves pre- 
ferred this method for reproducing their work, having, 
among other advantages, the ones that the artist was 
no longer restricted as to size in making his drawing, 
and al$o that he need no longer reverse figures and com- 
position. He was at liberty to follow his natural ten- 
dencies in drawing, whether large or small, the size of 
the reproduction being determined by the camera and 
consequently being made large or small with equal 
facility. 

THE HALF-TONE 

This "line block," "zinc etching," "zinco," as it 
was variously called, had practically every advantage 
of the wood block, and could even be used on coarser 
paper. But, like all other preceding forms of engraving, 
it could not produce gradations in tones except by lines 
and dots. Such surfaces as photographs, for example, 
could not be reproduced directly, but must be redrawn 
in pen or crayon. Any picture where tones were pro- 
duced by lines, however, or even very minute dots, 
could be reproduced by this "direct" process. Even 
the minute and almost microscopic dots of a lithograph 
picture or a pencil on coarse paper could be reproduced, 
and by using hard metal, such as copper, and printing 
carefully on fine paper, even the very fine lines of an 
etching could be reproduced also. In fact, most of the 
so-called "etchings" scattered broadcast at present in 
cheap publications are really only "zinc etchings," 
which are about the cheapest, instead of the most ex- 

[205] 



SCIENCE IN THE INDUSTRIAL WORLD 

pensive form of illustration they would be if they were 
real etchings. 

This form of reproducing pictures, known as the 
"direct " method, was soon succeeded by the discovery of 
a method employing the same principle but which could 
be used in reproducing such flat-toned pictures as the 
photograph. This ingenious process, perhaps the 
most wonderful as well as one of the simplest processes 
of reproduction, is what is known as the " half-tone " 
process, made so familiar in the last two decades by the 
illustrated magazines of every description, in which 
most of the pictures are made in this manner. 

This process differs from the foregoing in that a 
" screen' ' is interposed between the picture and the nega- 
tive in making the " screen negative" for printing on 
the metal plate to be engraved. For this reason the 
half-tone process is called the "indirect," in contra- 
distinction to the "direct" one. The principle of 
producing gradations in tone is accomplished by fine 
dots or lines in the one, just as in the other, only these 
dots are made artificially upon the negative and not on 
the picture itself, and are so minute that they are not 
noticeable except by careful scrutiny. 

If an ordinary piece of wire screen, such as is used on 
the screen-doors in summer time, is placed in close con- 
tact over a picture of any considerable size, it will be 
observed that, while the picture is somewhat obscured, 
it is still easily discernible ; and if it is held at a little 
distance it appears almost as distinct as without the 
overlying screen, the meshes of the screen practically 
disappearing. Obviously, a large surface of the picture 

[ 206 ] , 



REPRODUCTION OF ILLUSTRATIONS 

is no longer visible, being covered by the fine wires of 
the screen; yet the general effect remains the same. It 
is evident, therefore, that the visible parts of the picture 
actually seen are minute square spaces of various grades 
of tones and colors, each one represented in size by a 
mesh of the screen. The picture in this condition is 
simply a mosaic made up of a number of small squares. 

If each one of these squares is examined separately 
it will be found that the tone of each is practically uni- 
form, sometimes slightly darker on one side or the other 
as the tone of the picture grades from dark to light. 
This surface, then, is one of dots — the kind of a surface 
necessary for reproduction by the direct photo-engrav- 
ing process just described. 

Observing this and similar phenomena it seems to 
have occurred to several engravers, shortly after the dis- 
covery of the direct process of engraving, to attempt to 
produce such an effect with very minute dots of a fine- 
mesh screen upon the negative to be engraved. And 
this was finally brought to practical perfection by Dr. 
Max Levy, of Philadelphia, who invented a machine 
with which almost microscopic, but still uniform, 
parallel lines could be ruled upon glass. 

If anyone will take the trouble to hold any half-tone 
picture close to his eye he will observe, what may not 
have been apparent at the ordinary reading distance, 
that the picture is made up of innumerable small dots. 
This is the effect of the screen, and the homogeneous 
surface of color is really an aggregation of minute dots 
of color — a great mosaic, just as in the case of the picture 
with the wire screen over it. These dots, so inconspicu- 

[207] 



SCIENCE IN THE INDUSTRIAL WORLD 

ous but still the substance of the picture, are made by 
the glass screen which is the all-important agent in half- 
tone reproduction processes. 

This screen is made of two pieces of glass, ruled with 
minute parallel lines, so placed that they cross at right 
angles, giving the mesh-like appearance of the screen. 
To prepare such a screen, the surface of a piece of glass 
is coated with some substance analogous to the coating 
used on the surface of the metal plate by an etcher. 
This surface is then ruled by delicate machinery in 
minute parallel lines, the diamond ruling-point of the 
machine removing a minute line of the coating, but 
leaving a corresponding ridge of it between each line. 
These lines are at mathematically equal distances apart, 
and there are from about fifty to as many as four hun- 
dred to the inch. When ruled, the surface of the glass 
is treated to an acid bath, which eats out the surface 
of the glass in the paths made by the diamond point. 
When sufficiently etched the glass is cleaned, and an 
opaque pigment rubbed into the rulings. Another 
plate, treated in a similar manner but with the rulings 
running at right angles, is now fitted to the surface of the 
first one, the result being the checkered appearance seen 
in the half-tone print. 

To reproduce a picture by means of this screen, an 
ordinary negative is made just as in direct photography, 
except that the screen is interposed between it and the 
picture or object to be photographed. The resulting 
negative, which is called the " screen negative," shows 
the minute meshes on the screen, just as observed in the 
finished print. 

[208] 



REPRODUCTION OF ILLUSTRATIONS 

This negative is now laid upon a copper or zinc plate 
and treated in the same manner as the zinc etching just 
described. As the minute rulings of the screen were 
filled with a dark pigment that prevented the passage 
of light, it is obvious that the layer of sensitized film 
will be acted upon in minute checks representing the 
meshes of the screen. When this has been acted upon 
for a sufficient length of time, the copper plate is re- 
moved, inked, developed, and washed, this washing 
removing all the particles of the sensitized coating not 
hardened by the light. The plate is then dried, heated, 
and subjected to an acid bath which " bites" away the 
intermediate surface of copper about the dots. The 
plate thus finished is mounted type-high, and may be 
inked and printed in the same manner as ordinary type. 

Of course, in the actual practice of making fine half- 
tones the process is somewhat more complicated, al- 
though not differing in principle. For example, the 
engraver, wishing to produce lighter or darker effects, 
" stops out" certain portions, and " bites" others longer, 
to get the desired effect. But these are details, and this 
process has made it possible for an ordinary workman, 
having neither artistic taste nor any great degree of 
mechanical skill, to produce in a few hours, or even 
minutes, an engraving which gives a more faithful and 
natural reproduction of drawings or objects than is 
possible by the most skilful wood-engraver after weeks 
of hard labor. Furthermore, any number of such en- 
gravings may be made from the same negative. 

The result of the discovery of this simple process 
with its wonderful effects was the finishing blow to 
vol. viii. — 14 [ 209 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

wood-engraving, and except for certain ultra-artistic 
and commercial purposes, wood-engraving has become 
a thing of the past. The skilful wood-engraver of 
the older generation has been obliged to seek other 
means of earning a livelihood, although one field is still 
open to him to a limited extent. This is the " retouching, " 
or engraving, of the half-tone plate itself. It is found in 
practice that for very fine printing the half-tone plate 
can be greatly improved by engraving certain portions 
of it with a tool, just as in the case of the wood block. 
Good half-tone printing must be done on paper specially 
prepared with a surface to get the desired color-values 
in printing from the ordinary acid-etched plate. To 
facilitate this printing, and to get the best results, there- 
fore, the plate is sometimes " tooled' ' in places, the tool- 
ing of such blocks having now become the regular 
occupation of many former skilful wood-engravers. 
In the actual process of printing, the etched plates 
themselves are usually not used, duplicates of them 
made by "electrotyping" being generally employed, 
the original engraved plate being kept in reserve. This 
electrotyping-process is a simple one, it being possible 
to make as many duplicates as desired without injury 
to the original plate. To make such electrotypes an 
impression of the engraved plate is taken by pressing it 
firmly into wax or some other similar medium. The 
result is an exact cast of the engraving in the wax. 
This cast is then placed in an electric bath containing 
a solution of copper, from which the copper is deposited 
upon the surface of the wax as a thin film of metal, by 
the action of the electric current. This film of metal, 

[210] 



REPRODUCTION OF ILLUSTRATIONS 

which is an exact duplicate of the original plate, can now 
be strengthened by pouring lead or type-metal over its 
posterior surface, and is then ready for mounting type- 
high and printing. 

THREE-COLOR PROCESS OF REPRODUCTION 

Perhaps the most wonderful result of the discovery 
of reproducing pictures by the half-tone process is the 
possibility of reproducing pictures in color by the com- 
paratively simple process of superimposing three half- 
tone blocks successively upon a surface of color. The 
underlying principle, which is the basis of all three-color 
work, is the well-known fact that all colors, and all 
shades of color, may be produced by proper blending 
of the three primary colors, red, blue, and yellow. 
This is of course not apparent to the sense of sight, and 
the ordinary painting, with its purples, greens, and 
browns, to say nothing of the blacks and whites, seems 
to be an aggregation of scores of colors having little re- 
lation to each other. But as a matter of fact this is an 
optical illusion, the seemingly endless varieties of colors 
being simply blendings in certain proportions of the 
three primary colors. This optical illusion is no more 
wonderful than the fact that ordinary white light, which 
appears to have no color at all, is in reality a blending 
of many colors; but from the nature of the case it is 
more tangible. 

As early as 1861 the possibility of producing any 
desired color by superimposing the primary colors in 
exactly the right proportions was suggested by the 

[211] 



SCIENCE IN THE INDUSTRIAL WORLD 

English scientist, J. Clerk-Maxwell, but in actual prac- 
tice many difficulties were encountered in producing the 
desired effects by such a process. A great number of 
things interfered with the actual workings when it 
came to apply pigments to the paper. For example, 
the colors used must necessarily be absolutely pure 
reds, blues, and yellows; and such colors, containing 
no trace of any other color, were difficult to produce. 
A great difficulty was also encountered in the mechanical 
part of producing practical blocks for printing. So 
that it was not until 1881 that practical color-printing 
became possible. 

Experimenters both in Europe and America had been 
working on the problem, but the first blocks that were 
actually practical for this kind of work were perfected 
by F. E. Ives, of Philadelphia, in 1881. This date, 
therefore, with that of the discovery of the half-tone 
process shortly before, marks an epoch in the history 
of illustration — an epoch of perhaps greater improve- 
ments than any since the discovery of the possibilities 
of reproducing pictures by woodcuts or metal plates. 

Knowing that every picture in color, no matter how 
complicated its scheme, is simply a peculiar arrangement 
of the three primary colors, it is obvious that if some kind 
of substance which would allow the passage of the rays 
of one of these colors and exclude those of the others, 
could be found, then the position and amount of this 
particular color might be determined. This of course is 
not possible by the ordinary sense of sight any more 
than it is possible for the unaided eye to determine the 
composition of ordinary light. But by the use of prisms 

[212] 



REPRODUCTION OF ILLUSTRATIONS 

in such an instrument as the spectroscope, as is well 
known, this analysis of the composition of substances 
may be made. Acting upon the knowledge of these 
facts, attempts were made to produce transparent "fil- 
ters " which, when used in connection with a photographic 
plate, allowed one of the primary colors of a picture to 
act upon the plate while excluding the other two. These 
experiments finally proved successful with the result 
that practical filters were made, allowing the transmission 
of the rays of any one of the three primary colors while 
excluding the others. Such filters w T ere made in various 
ways, sometimes of transparent colored glass, or glass 
coated with some substance of the required tint, or again 
of a hollowed glass containing a liquid of the proper 
color. 

In using these color filters, or screens, in the actual 
process of three-color work, the photographer makes 
three separate negatives, taking each from exactly the 
same position, one negative being made with a yellow 
filter placed between it and the picture to be reproduced, 
a second with a blue, and the third with a red. These 
negatives are developed and three separate half-tone 
blocks made from them, each block representing by its 
gradation of light and shadow the amount of yellow, 
blue, and red, respectively, contained in the picture. 
The blocks are then placed in the press and printed 
successively upon the surface of paper, using yellow, 
blue, and red ink, the result being an exact reproduction 
of the original picture with the colors faithfully produced, 
if sufficient time and skill are used. 

Theoretically it makes no difference which color is 

[213] 



SCIENCE IN THE INDUSTRIAL WORLD 

printed first, or the order in which the other two are 
superimposed upon it; the result should be the same 
in any case, as the total amount of pigment covering 
any point in the picture will be the same. In actual 
practice, however, owing to mechanical difficulties, and 
for other reasons, this order of imposing the blocks is of 
great importance, the best results being obtained by 
certain definite order in printing certain pictures which 
would be less satisfactorily reproduced if this order were 
reversed. 

It is obvious that one of the great difficulties in such 
a process is that of determining the exact shade of 
yellow, red, and blue pigment to be used in the print- 
ing, but this is usually done by practical experiment. 
Another difficulty is the matter of accurately registering 
each block so that it prints in exactly the same position 
as the other two. But these difficulties have been 
practically overcome so that at present three-color pic- 
tures of mediocre quality can be made with relative 
cheapness and expedition; while fine pictures faithful 
in color and extremely artistic in effect may be produced 
at a relatively low price. 

Most good three-color engravers have their own 
special methods of making filters, and preparing and 
printing the cuts. In skilful hands a great latitude is 
allowable in the selection of colors for the different 
filters, inks, etc., and many engravers prepare their 
own filters and inks. One prominent firm, for example, 
uses green, violet, and red filters, and produces beauti- 
ful effects by this combination. 

A great difficulty is always found in producing clear, 
[214] 



REPRODUCTION OF ILLUSTRATIONS 

snappy blacks and clear intermediate grays. To do 
this a fourth printing with black ink is sometimes used, 
the " three-color " work then becoming really four-color 
printing. The principle involved, however, is the same 
as in three-color printing, the extra black being applied 
to improve the blacks in the picture which have a ten- 
dency to become muddy, and not clear and sharp. 

The comparative merit of pictures reproduced in color 
by lithographic processes and those reproduced by the 
three-color process is determined, commercially at least, 
by the fact that only three printings are necessary for 
the reproduction of any picture by the photographic proc- 
ess, whereas to get the same effect by lithography it is 
always necessary to make several more separate print- 
ings than these, sometimes as much as forty separate 
impressions for very fine facsimile work, although 
of course such a number is unusual. 

Waiving the question of mechanical advantages or dis- 
advantages, however, it may be said in a general way that 
artistic effects are better represented in the three-color 
process, a certain hardness in the colored lithography 
being practically unavoidable. For the reproduction 
of purely artistic designs such as paintings, therefore, 
artists very generally prefer the three-color process to 
the lithographic. 

On the other hand, when exact facsimiles in color are 
to be made, where scientific accuracy rather than ar- 
tistic effect is desired, lithography is still superior to 
three-color process work. The remarkable results 
that may be obtained by this lithographic process of 
many printings are such that in cases where an absolute 

[215] 



SCIENCE IN THE INDUSTRIAL WORLD 

facsimile is desired, regardless of cost, it is possible to 
produce such a facsimile so closely resembling the orig- 
inal in every particular that it requires the eye of an 
expert, sometimes aided by the microscope, to distin- 
guish the original from the print. Some of the ancient 
Egyptian documents, for example, have been so faith- 
fully reproduced, both as to the color and design of the 
papyrus as well as the painting upon it, that only by the 
closest scrutiny can the difference between the original 
and the lithographic copy be detected. 

There are two distinct fields, therefore, for three- 
color and lithographic color-work. The perfection in 
lithographic printing, in its particular field, produces 
results which are as yet not attainable by any other 
method. Three-color work, on the other hand, is in its 
infancy. But it has been making such rapid strides 
during the last ten years that no one at present is 
warranted in predicting the limits of its possibilities. 
Even now it has practically driven lithography out of 
certain fields; and it may be only a question of time, 
and perhaps a very short time, before it will supersede 
the older process in every field. 

The process of three-color work as just described 
represents the general method in use, and the prin- 
ciples involved. Needless to say there are endless varia- 
tions in details in applying the process. In some of 
these processes the half-tone screen is in use; in others 
it is used only in certain parts of the picture; but the 
number and variety of these variations do not affect 
the general principle involved and need not be dwelt 
upon here. 

[216] 



REPRODUCTION OF ILLUSTRATIONS 



INTAGLIO PROCESSES 

The best representation of the older intaglio process 
of reproducing pictures is a steel-engraving where the 
printing-surface is set below the surrounding portion 
of the field, rather than the reverse as in the case of the 
ordinary printing-block. Perhaps the best modern 
representation of this process is what is known as the 
photogravure. And in many respects the photogravure 
may be said to hold the same relation to the modern 
half-tone that the steel engraving does to the woodcut 
of former times. 

The photogravure, like the copper and steel plate, 
is made by digging out certain portions of the metal 
plate, but the process of doing this is no longer a purely 
mechanical one, modern photographic and chemical 
methods being requisitioned for the purpose. In making 
the plate for the photogravure a screen is used, but this 
screen is not made of ruled glass as in the case of the 
half-tone, but is one in which the necessary dots are pro- 
duced by a fine layer of bitumen dust. In this process the 
fine dots made by the bitumen dust take the place of the 
little checks or points made by the half-tone screen. 

As a photogravure is made with a depressed printing- 
surface instead of the ordinary raised one, a positive 
is used for printing in place of a negative. The metal 
plate so treated is then placed in a bath of some such 
substance as perchloride of iron which bites out the 
metal to the desired depth. 

The prints made by this process present a fine granu- 
[217] 



SCIENCE IN THE INDUSTRIAL WORLD 

lar surface and more closely approach facsimile repro- 
ductions than perhaps any other form. But the making 
of such prints from photogravure plates is a slow task 
requiring special printing and considerable skill, making 
such reproduction too expensive for use as ordinary il- 
lustrations. Furthermore, since each picture must be 
printed separately, the photogravure process cannot be 
used in connection with type. 

While the majority of photogravure processes are 
based on the principle of the sunken printing- surface, 
it is possible to reverse this, making the photogravure 
plate as relief work. In this process the granular effect 
is obtained by the use of the bitumen dust the same as 
in the other, but the relief effect is obtained by certain 
processes of depositing particles of metal rather than 
by biting out surfaces with an acid. There is little choice 
between the results of these two methods. 

Quite recently several secret processes of reproducing 
pictures have been invented which represent a middle 
ground between the relatively slow and expensive pho- 
togravure process and the cheap and rapid half-tone. 
The results obtained by these processes are somewhat 
inferior to photogravure work, while the expense and 
speed involved in their production compare favorably 
with a better class of half-tone work. The exact method 
of producing such illustrations is not generally known, 
but it is understood that no new principles are involved, 
and the secret lies mostly in the perfection of the print- 
ing-machine rather than in any new departure from 
well-known engraving-processes. 

In the foregoing description of the development of the 

[218] 



REPRODUCTION OF ILLUSTRATIONS 

various processes for reproducing illustrations, only the 
broadest general principles involved have been touched 
upon, giving only sufficient details to illustrate the ap- 
plication of these principles. A complete account of the 
various modifications in the applications of these prin- 
ciples to practical engraving would require many closely 
written volumes, for almost every engraver has his 
own special method of doing things to get certain well- 
defined results, but these, although somewhat inter- 
esting in their details, are not essentials of the develop- 
ment of engraving. 



[219] 



X 

PHOTOGRAPHY IN ITS SCIENTIFIC ASPECTS 

IN the development of photography, at least, history 
has repeated itself under peculiarly similar circum- 
stances. Two of the most important discoveries 
in this field, one made by Daguerre early in the nine- 
teenth century, and the other by Becquerel just at its 
close, were made quite accidentally, and in practically 
the same manner. Becquerel discovered radio-activity, 
and Daguerre discovered a practical method of develop- 
ing photographic plates, by accidentally leaving photo- 
graphic material in a dark chamber. 

The fact that certain chemicals quickly change color 
when exposed to light was known for half a century 
before practical photography was invented, the Swedish 
chemist, Karl Wilhelm Scheele, having discovered this 
about 1780. Curiously enough, it was this same scien- 
tist who discovered that color could be removed, as well 
as produced, chemically, both these discoveries being of 
the greatest commercial importance. In experimenting 
with the silver salts Scheele found that the color of a 
solution containing these salts could be changed by 
rays of ordinary light, or by light passing through blue 
glass, although the color was not affected by light passing 
through red or yellow glass. A few years later, Count 
Rumford, the discoverer of the fact that heat is a form 

[ 220] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

of motion, attempted to show that the changes in chem- 
icals attributed to the action of light by Scheele were 
really due to the action of heat; but he was unsuccessful 
in these attempts, Scheele's contention being strength- 
ened rather than weakened by Rumford's arguments. 

The first practical application of Scheele's discovery 
to picture-reproduction seems to have been made by 
Thomas Wedgwood, a member of the famous Wedg- 
wood family, of England, in 1802. His process, which 
was first described in the Journal of the Royal Institu- 
tion, was to moisten paper or white leather with a solu- 
tion of silver nitrate in a dark room, and then expose 
the moistened surfaces to sunlight. In this manner 
the colorless moistened portions of the sheets quickly 
became black if exposed to the full rays of the sun, 
although they could be kept indefinitely without change 
of color if screened from the light. This discovery sug- 
gested the possibility of reproducing pictures, or " shad- 
owgraphs," as they were called, and Wedgwood pointed 
out the advantages of such a process in reproducing 
prints from transparencies on glass. 

Here was the germ of the idea from which practical 
photography has been evolved. But there were still 
many intermediate discoveries to be made before even 
the crudest photographs were possible. At that time 
there was no means of forming a camera-image, or 
" negative," the nearest approach to a camera being the 
camera obscura in which an image was shown upon 
ground glass. Nevertheless the possibilities of the dis- 
covery were recognized, and Sir Humphry Davy made 
some experiments with the camera obscura; but noth- 

[221] 



SCIENCE IN THE INDUSTRIAL WORLD 

ing like satisfactory prints could be made, and as no 
means of "fixing" the prints had been discovered, 
Wedgwood's discovery was looked upon as valuable 
simply as a scientific demonstration. 

TENTATIVE EFFORTS 

But the possibilities of this discovery, and similar 
ones that might result from it, stimulated scientists, and 
guided the trend of thought along channels leading to 
photography. Within the next decade these efforts bore 
good fruit. By 1 8 14, a Frenchman, Nicephore de Niepce, 
had discovered a method of making permanent pho- 
tographs by a crude and complicated process. He 
coated the surface of a metal plate with a solution of 
oil of lavender, which, after being allowed to dry, was 
exposed to an image made in a crude camera. After 
such an exposure lasting several hours a faint image 
appeared on the plate which could be intensified and 
strengthened by a complicated process of development 
with more oil of lavender and bitumen. But even at 
best only a very faint image could be thus reproduced, 
although these first pictures of Niepce are very properly 
regarded as the first photographic pictures ever made. 

The process of actually making these sun-prints was 
not revealed for some time by Niepce, who recog- 
nized the possible commercial value of his process if 
perfected, and made his experiments secretly. His 
task proved an arduous one, however, and it was 
another full decade before he had accomplished any- 
thing like practical results. Then, having perfected 

[ 222 ] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

and improved his process until he was able to make 
pictures on metal in many ways resembling the modern 
tin-type, he sent an account of his discovery to the 
secretary of the Royal Society of London, together 
with some specimens of his work. But the actual 
process by which the pictures were made was not 
revealed in this document, and on this account the Royal 
Society as a scientific body, although greatly interested, 
could not publish it. 

Just at this time a fellow countryman of Niepce's, 
whose name was later to be far better known in the 
history of photography, became interested in the sub- 
ject. This was Louis Jacques Mande Daguerre, a 
scene-painter, who was famous at the time for his 
handling of lights and shades, and whose attention 
had been directed to the subject of photography by the 
remarkable effects he was able to produce with light 
projected through colored glasses. At that time he had 
done nothing with the subject of " heliographic pictures," 
as they were called, but when a letter came to him from 
Niepce, in 1827, suggesting that a partnership be es- 
tablished between them, he readily entered into such an 
arrangement. 

The new firm was soon able to reproduce pictures of 
various kinds on metal, and also upon glass and porce- 
lain, but the process used was too complicated and te- 
dious for practical commercial purposes. Nothing but 
stationary objects in bright sunlight could be reproduced, 
and then only after weary hours of exposure to a sen- 
sitized plate in a camera. Ordinary landscapes re- 
quired an exposure of from seven to ten hours — prac- 

[223] 



SCIENCE IN THE INDUSTRIAL WORLD 

tically a whole day, although "this time could be 
shortened by half in the case of such objects as white- 
marble monuments." 



THE DAGUERREOTYPE 

This process was so exasperatingly near a really prac- 
tical method of making pictures that Daguerre and 
Niepce strained every nerve to bring it to perfection, 
or at least to a stage of commercial practicality; but 
after six years of ceaseless struggle, Niepce died, leaving 
the riddle apparently as unfathomable as ever. Yet, 
had he but known it, he was on the very threshold of 
the discovery; and five years later Daguerre finally 
accomplished what Niepce had missed by so narrow a 
margin. In 1839, Daguerre announced to the French 
Academy the process that was thenceforth to be famous 
as the daguerreotype process, by which a camera image 
could be reproduced by the action of light and chemicals 
alone, and by a relatively short exposure. 

The announcement of this process created a sensa- 
tion in the Academy. There was no doubting the evi- 
dences of their own senses, and all the members were 
apparently in accord in their expressions of admiration 
and astonishment. Arago, the leading physicist of 
France, spoke in glowing terms of the possibilities of 
the new discovery, and made predictions as to its future 
usefulness that have been more than fulfilled in recent 
years. And as the French Academy had given the cue, 
other learned bodies all over the world echoed its senti- 
ments. Nor were the scientists the only persons to recog- 

[224] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

nize the possibilities of the new art. Quite as much inter- 
est and enthusiasm were shown by the generality of 
people all over the world, although as yet the process 
was so complicated as to be quite beyond the grasp of the 
ordinary operator. But anybody could understand that 
there was something closely akin to the miraculous in 
any device, no matter how complicated, whereby a 
more perfect picture could be made in a few minutes 
than could have been made hitherto by any known 
process in days or weeks. 

And yet, as said a moment ago, the process was only 
a slight modification of the one first discovered by Niepce 
— slight, but of most vital importance. It was simply 
the discovery that if a silver surface, or a silver-plated 
one, was acted upon by the fumes of iodine, it became 
so sensitized that it was acted upon more quickly by 
light than any substance heretofore discovered. Instead 
of requiring hours of sunlight exposure to reproduce 
the camera image, only about three minutes were re- 
quired by the new process; and even interiors could 
be taken in half an hour. 

As compared with the older method of Niepce this 
process seemed rapid indeed ; but it was still very com- 
plicated and defective in many ways, and it was while 
endeavoring to simplify and shorten it still more that 
Daguerre accidentally stumbled upon the discovery 
that made commercial photography possible. Being in- 
terrupted in his work one evening, he was obliged to 
leave some exposed but as yet undeveloped plates until 
the following day before completing them. For safe- 
keeping he locked these in a cupboard containing chem- 
vol. \m- 15 [ 225 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

icals of various kinds. On examining them the following 
morning he found to his astonishment that they were 
completely developed, although nothing had been done 
to them since their exposure. There was only one 
explanation possible : the fumes of some of the chemicals 
in the cupboard must have been responsible. And by a 
careful process of elimination Daguerre finally deter- 
mined that the fumes of mercury had produced the 
effect. Carrying these experiments a little further he 
found that by exposing his sensitized plate in the ordi- 
nary manner and then holding it face downward over a 
basin of warmed mercury, the image appeared quickly, 
and could be made permanent by dipping the plate in a 
solution of hyposulphite of soda. This may be con- 
sidered the starting-point of modern photography. 

As there was no secret about the process used in 
making these photographs, scientists all over the world 
were soon duplicating Daguerre's experiments. Before 
the eventful year closed, two Americans, Morse and 
Draper, had succeeded in making a portrait of a person 
— the first ever taken. In making this first portrait the 
operators powdered the face of the sitter and posed him 
in bright sunlight, with eyes closed, for a period of half 
an hour. Several attempts were made before anything 
like a satisfactory result was obtained, the great diffi- 
culty encountered being the strain of the glaring sunlight 
upon the sitter's face, which was almost unbearable. 
Finally a glass jar containing a blue-colored solution 
was placed between the face and the sun, and the strain 
relieved in this manner, so that a fairly good, if some- 
what ghastly, portrait was made. 

[226] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 



talbot's "calotype" process 

Meanwhile another European scientist was making 
important discoveries in the same field that were to 
prove quite as momentous a little later, as those of 
Daguerre. Fox Talbot in England, about the time 
that Daguerre announced his discovery, discovered a 
process of photographing on paper, which he called 
"calotype" or the "beautiful picture" process. This 
did not differ very greatly in general principle from the 
process of Daguerre, save in the fact that paper was 
used in place of metal plates. But Talbot's ' ' calotypes ' ' 
were the forerunners of modern paper photographs, 
just as daguerreotypes are the direct ancestors of modern 
negatives. 

In Talbot's process, the surface of the paper was pre- 
pared by brushing it over with a solution of silver nitrate, 
and allowing it to dry. It was then dipped in a solution 
of potassium iodide for two or three minutes, until silver 
iodide was formed, and was then treated with a solu- 
tion of what is known as " gallo-nitrate of silver." If 
the paper so treated were exposed to the camera image 
for a few minutes, this image would be reproduced, as in 
the case of the silver-surface plates of Daguerre, the 
developing-process being hastened by soaking the paper 
in more of the gallo-nitrate solution. The paper was 
then washed thoroughly, dipped in a solution of potas- 
sium bromide for a few minutes, and again washed and 
dried, a permanent paper print, or photograph, being 
the result. 

[227] 



SCIENCE IN THE INDUSTRIAL WORLD 

Although a little later it was decided by a legal techni- 
cality in a lawsuit that the patent rights of this process, 
and therefore presumably the priority of discovery, be- 
longed to Fox Talbot, there seems to have been another 
and earlier discoverer of a "gallo-nitrate" process. 
This was the Rev. J. B. Reade, a clergyman who had 
become much interested in the new studies of light- 
pictures. But the courts decided the case in favor of 
Talbot on the ground that Reade's discovery had never 
been legally published ; and, all things considered, this 
decision seems an eminently just one. For the gallo- 
nitrate process as used by Reade, although an important 
part of the Talbot process, was by no means the entire 
calotype process as Talbot perfected it. And while 
Reade's discovery may have helped Talbot, it was by no 
means responsible for his final results. 

There is no reason to believe that Talbot ever at- 
tempted to belittle the part taken by the clergyman in 
the discovery of the gallo-nitrate process, for at that 
time the name Fox Talbot was too well known in the 
scientific world to need further advancement by claim- 
ing the work of others. It may be recalled that it Was 
he who, with Rawlinson and others, helped to decipher 
the Assyrian hieroglyphics — a feat quite as wonderful 
as were his discoveries in photography. 

Naturally, the thing most sought for in this new field 
of art-science was some substance that would render 
plates more sensitive, and, in 1841, an experimenter by 
the name of Goddard made the discovery that bromine 
vapor acted in this manner. In this same year, also, M. 
Fizeau invented the process of toning or gilding photo- 

[228] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

graphs with a solution of gold, greatly increasing the 
richness of their tones. There were, besides these 
important discoveries, a number of minor ones that 
helped in developing the process. But still it was too 
complicated for anyone, other than a trained scientist, 
to attempt successfully — was, indeed, still in the experi- 
mental stage, and of little account commercially. But 
just before the century turned the half-way point, 
another important discovery was made which placed 
practical photography within the grasp of any ordinarily 
intelligent operator, even one without any special 
scientific training. 

GLASS NEGATIVES 

This discovery, or invention, was that of the now fa- 
miliar glass negative, from which prints could be made. 
The inventor was Niepce St. Victor, a nephew of Da- 
guerre's partner, who had been trained by his uncle, and 
who had continued the investigations begun by the 
elder Niepce. In his experiments he used glass plates 
sensitized by iodized albumen, and 'obtained fairly satis- 
factory results; but this process was soon improved by 
Blanquart and Le Gray. The essential part of their 
process consisted in treating a glass plate with a mix- 
ture of the whites of eggs containing potassium iodide 
and potassium bromide. This solution was first dried on 
the plates, and was then sensitized by treatment for a 
few minutes with a solution of nitrate of silver. Such 
plates were exposed to the camera image while still wet, 
and then developed in a gallic-acid solution. They were 

[229] 



SCIENCE IN THE INDUSTRIAL WORLD 

extremely delicate and liable to injury before being 
dried, but when once fixed and thoroughly hardened 
were practically the same as modern glass negatives. 
Still, there was a tendency for the film to peel from the 
glass during the necessary manipulation, and this was 
not overcome until the following year, when Frederick 
Scott Archer, of London, discovered a means of remedy- 
ing this by the use of collodion. This substance made 
a film so tenacious that it could be handled without fear 
of injury. Indeed, it may be said that it was this par- 
ticular discovery, rather than the preceding, that made 
commercial photography possible. 

While these various improvements in photographic 
plates were in progress, lens-makers had been busy with 
the improvements in cameras; and by the time the 
Archer collodion plate was perfected there were good 
cameras in which to use it. The entire process of 
photography was still a complicated one, judged by the 
modern standard of dry plates and " daylight devel- 
opers"; but it required patience rather than skill or 
scientific training, and within a few years after Archer's 
announcement of his discovery almost every city, town, 
and hamlet over the civilized world, had its " photograph 
gallery." Indeed, the "craze" was quite as universal 
at that time, as was the similar one half a century 
later when the a push the button" snapshot-camera 
came into existence. 

The cardinal defect of the collodion process lay in 
the fact that the plates had to be freshly made and kept in 
a moist state while using. This meant that the photog- 
rapher could only operate near his dark-room labora- 

[230] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

tory, where he used his various chemicals. Field opera- 
tions, therefore, were seldom attempted. But, in 1854, 
Spiller and Crookes published in the Philosophical 
Magazine the account of a method of keeping plates 
moist for several days that made field operations pos- 
sible. The basis of this process was the use of the salts 
of zinc which have the property of imbibing moisture 
from the atmosphere. By incorporating a certain 
quantity of these salts in the moist film of the plate, 
drying was prevented for several days. So that by 
using a somewhat large and clumsy set of plate-holders, 
specially made for the purpose, the photographer could 
make extensive excursions; and field photography 
soon became popular. 

COLLODION-EMULSION PROCESS 

After the discovery of this last phase of plate-making 
little progress was made in photography for a decade. 
Then, in 1864, Bolton and Sayce invented their "col- 
lodion-emulsion process/ ' and 'a new impetus was 
given to the art. It will be recalled that in the processes 
for coating the plates, used heretofore, it was necessary 
to coat the plate with the collodion mixture of the bro- 
mides, dry it, and then dip it in a solution of silver 
nitrate. In the new "emulsion" process the emulsion 
contained all the chemicals for the necessary reaction, 
so that the plate could be made simply by pouring the 
emulsion over the surface and allowing it to set. But, 
when first introduced, this process was found to have 
a serious defect — the plates frequently "fogged" in 

[231] 



SCIENCE IN THE INDUSTRIAL WORLD 

the developing process in an unaccountable man- 
ner. But this was soon corrected by the discovery 
of two Americans, Cary Lea of Philadelphia, and 
W. Cooper of Reading, Pennsylvania, that all this 
could be overcome by the addition of a little acid to 
the solution. 

It was presently discovered that the addition of the 
acid made the plates much more rapid, although any- 
thing like " snapshot" photography was not possible. 
But in 1873 Col. Stuart Wortley found that when a 
strongly alkaline developer was used, plates need only 
be exposed a fraction of the time ordinarily required, 
although, as yet, such time for exposures did not cut 
the second into thousandths, as at present. This dis- 
covery had a peculiarly stimulating effect upon both 
scientists and practical photographers, and other im- 
portant discoveries followed in rapid succession. 

The following year, a famous Belgian chemist, M. J. 
S. Stas, published an article entitled Researches with 
Chloride and Bromide 0} Silver, in which he pointed 
out that bromide of silver could exist in at least six 
different states, each state having peculiar properties 
and different sensitiveness to the action of light. But 
this paper was written from the standpoint of the 
chemist rather than that of the photographer, as Stas 
himself was not personally interested in the art; and 
for the moment it went unnoticed by the photographers. 
In point of fact, however, it contained the key to the 
scientific facts upon which modern rapid photography 
is based ; and a few photographer- scientists, recognizing 
the possibility of the suggestions contained in it began 

[232] 




THE FLYING MACHINE OF MR. GLEN H. CURTTSS 

This is a wonderful example of instantaneous photography. The machine appears to 
be stationary, although in reality moving at the rate of almost fifty miles an hour. With 
this type of machine Mr. Curtiss won the International speed contest at Rheims, France, 
August 28, 1909. He made a flight of twenty kilometers (12.42 miles) in 15 min. 
;o4 sec. 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

experiments along the lines it suggested. Among these 
was Dr. D. von Mockhoven, of Ghent, and five years 
later, in 1879, he announced a process of making rapid 
dry plates by adding a solution of ammonium bromide 
to the ordinary gelatine emulsion that had very generally 
replaced the collodion emulsion by that time. This 
process he credited to the suggestions made in Stas' 
paper of five years before, calling attention to this im- 
portant document in the history of photography that 
would otherwise have been generally lost sight of. 

It is from this year, therefore, that we must reckon 
the beginning of rapid dry-plate photography. By this 
time the wet collodion plate had practically disappeared, 
replaced by the dry gelatine plate; and Mockhoven's 
discovery, with those of other scientists and practical 
photographers, made possible the fraction-of-a-second 
negative, and paved the way to the "You push the 
button" camera. 

The modern era of photography may be said to begin 
with the discovery of Mockhoven and his associates. 
Yet one more step was necessary to give photography 
the impetus for becoming the popular fad that it has 
remained for the last fifteen years. This step was the 
stroke of genius of the man who conceived the idea of 
using a flexible transparent film in place of the ordinary 
glass-plate negative, and rolling a number of these into 
a coil so that several pictures could be taken without 
bothering with plates — the " kodak" idea, that has since 
carried the world by storm. This happened about 1888, 
and the amazing flood of improvements — cartridge 
cameras, daylight-loading cameras, daylight-developing 

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SCIENCE IN THE INDUSTRIAL WORLD 

machines, and a score of other innovations — that have 
come into the market since that time, are so familiar 
to the majority of persons that it seems superfluous and 
unnecessary to dwell upon them here. It will be con- 
sistent with our purpose to consider, instead, another 
important though much less familiar field, which may at 
any time be brought to a stage of practical perfection 
that will make the present-day methods seem as anti- 
quated as those of Daguerre do to-day. I refer, of course, 
to the methods of so-called "color photography." 

PHOTOGRAPHING IN NATURAL COLORS 

To the average layman the idea of the photography 
of color is probably some method by which the color 
of objects may be reproduced as correctly and as auto- 
matically as are the shapes, and it must be stated at 
once that such a process, while the subject of much 
search, has never been even partially discovered, nor 
have scientists been able to discern any course of pro- 
cedure that would lead to this end. 

A recent writer on the subject has summed up the 
present status of the photography of color, which, as he 
states, is "always a compromise." 

"The methods of both the past and the present 
naturally fall into two classes. The less important 
division includes methods in which a single homo- 
geneous surface is employed, while in the larger di- 
vision the surface is multiple or non-homogeneous. 
The first is generally an attempt to get as near as pos- 
sible to the simple color photography" (that is, such 

[234] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

a process of actual color reproduction as is mentioned 
above), "while the second is entirely indirect in that 
it does not aim at producing color at all, but only at 
automatically locating suitable dyes or inks." 1 

Thus, we must understand from the outset that the 
term "photography of color" is entirely a misnomer. 
Color never has been, and perhaps never will be, 
photographed. Nevertheless, extremely interesting and 
valuable results have been obtained by means of the 
above-mentioned "compromise," and as the recent 
perfection of processes has brought color photography 
well within the amateur's field of activity, the subject 
is worth some detailed consideration. 

Alexandre Edmond Becquerel, a French physicist 
noted for his researches on light, seems to have been 
the first to take up specifically the matter of color 
photography. He began in 1838, although he did 
not give the world any account of his achievements 
until ten years later. Becquerel took a silver plate and 
produced on its surface, by chemical and electrolytic 
means, a layer of silver chloride. With the plates 
thus treated he succeeded in reproducing "with a con- 
siderable measure of success the colors of brightly 
dressed dolls and highly colored designs besides the 
solar and electric -arc spectra," but the colors were not 
permanent, and the investigator could find no means 
of "fixing" them satisfactorily. 

What was the nature of these colors — were they 
actual pigmentary matter due to a change in the sur- 
face coating, or were they "interference" colors pro- 
duced by "standing" light waves? Before answering 

I 235 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

this question it may be necessary to explain what a 
"standing" wave is. 

If light waves in motion are reflected back in the 
direction from which they come, it is evident that the 
returning ones will constantly meet those that are 
advancing. At the points of contact, therefore, a 
series of waves, whose crests rise and fall but cannot 
move in either direction, owing to the counteracting 
of the forward and backward impulses, will be pro- 
duced. These are the standing waves. At such sta- 
tionary points the light will be interfered with or 
quenched, and thus there will result a "series of lay- 
ers of light with intervals of darkness half a wave- 
length apart." 

Now, several scientists, among them Zenker, of 
Berlin, believed that this interference or quenching of 
light was the explanation of the colors on BecquerePs 
plates. The German physicist explained that "the 
silver-chloride coating of the plate is so affected by 
the light that metallic silver is produced in layers with 
intervals of no chemical change which correspond to 
the parts where the light is quenched by interference.' ' 
He assumed, and his assumption was afterwards 
proved to be correct, that metallic silver was produced 
because the successful reproduction of the colors re- 
quired a strong reflecting surface, and he further 
developed his theory by stating that these silver layers 
of high reflecting power reflected "only, or chiefly, 
light of the same wave-length (or color) as the light 
which produced the layers when they are illuminated 
by white light." In other words, BecquerePs colors 

[236] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

were merely the result of an intricate incidence and 
reflection of light, with the consequent interference, 
and not pigmentary matter at all. 

Without going into the discussion, which was long 
and very technical, it is only necessary to state that 
it has been finally shown that "the colors produced 
by Becquerel's process were found to be chiefly in- 
terference colors due to the action of the standing 
waves, but there was pigmentary matter also present," 
the latter being due to the subchloride of silver, though 
why "this should be changed by colored light into a 
substance that has some approach to the color of the 
light that falls upon it is a problem still unsolved." 

Prof. Gabriel Lippmann of Paris, in 1891, proposed 
a direct method of color photography, which, like that 
of Becquerel, is based on the production of interference 
layers in a photographic plate having a film sensitive 
to all colors and a good reflectory surface to send back 
the incident light. This surface was obtained by a 
slide filled with mercury which backed up the film. 
The results were never entirely satisfactory although 
the process was improved upon by later experimenters. 
It required very delicate adjustments and long ex- 
posures. This method must not be confused with 
the newer process of Professor Lippmann, announced 
in 1906, which will be described later. It is of quite 
another nature. 

In 1 86 1, Clerk-Maxwell demonstrated the possibility 
of projecting colored objects by means of three colored 
plates, red, yellow, and blue, basing his experiments 
upon the fact that all colors in nature may be simulated 

[237] 



SCIENCE IN THE INDUSTRIAL WORLD 

to the eye by a proper blending of these three colors. 
If three-color filters, made respectively of these three 
colors, were used, and negatives made by means of them, 
it would seem theoretically possible, at least, to reproduce 
colored objects by staining the three negatives thus 
made, red, yellow, and blue respectively, and super- 
imposing them so that they are accurately registered. 
As a matter of fact that is what is really done by many 
of the most successful three-color photographic processes 
— practically the same method as used in three-color 
process printing, referred to in detail in the chapter on 
three-color printing. 

In the actual practice of three-color photography 
many difficulties have to be overcome, and it is at best a 
tedious process. Three exposures must be made, and in 
making these the camera must be in exactly the same 
position for each negative. For a long time the difficul- 
ties to be overcome in this seemed insuperable, but Mr. 
F. E. Ives, of Philadelphia, has invented a slide-carrier 
for this purpose which works admirably; and Mr. 
Sanger-Shepherd has invented a single-lens camera by 
which all three negatives are taken at a single exposure. 

The length of time for exposures with the different 
color-filters is important, and the time required is much 
longer than for ordinary normal exposures. Generally 
speaking, exposures through the blue filter are about a 
hundred times more than normal length, the green or 
yellow two hundred times, and the red three hundred 
times. If the normal exposure were ten seconds, there- 
fore, the total time required for exposures through the 
color-filters alone, without deducting any time lost in 

[238] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

changing, would be something like an hour and 
three quarters. But this time is not constant, and 
as a rule test-negatives are made and developed 
with various filters before the final negatives are 
taken. 

It is obvious that when the negative is exposed to light 
coming through each of these niters, impressions will 
only be made and necessary deposits formed in develop- 
ment, at such points indicated by the position of certain 
colors. When such negatives are developed, only such 
positions of the object appear as are represented by the 
color in question. If positives are made from such 
negatives, and these stained red, green, and blue, re- 
spectively, according to the filter used, a transparency of 
the object photographed may be made, reproducing the 
natural colors with great fidelity. 

Sanger- Shepherd and others have perfected a process 
whereby prints may be made from these positives by the 
use of colored inks. The gelatine representing the 
primary color on each plate is slightly raised, and will 
absorb the ink as required. By carefully registering 
each of these impressions beautiful colored photographs 
may be made. To reproduce and print such colored 
photographs, however, is quite beyond the range of the 
ordinary amateur photographer. 

Generally speaking, all indirect color photography 
is based upon some such artificial and arbitrary sep- 
aration of color, and the achieved results have been 
obtained by working in two different ways; first, by 
the production of three images, one for each of the 
required colors, and, second, by the production of a 

[239] 



SCIENCE IN THE INDUSTRIAL WORLD 

single image taken and looked at through a tri-colored 
film. 

With the three images or records made by three 
exposures through colored screens, there are, again, 
two ways of forming the picture. By means of a set 
of three optical lanterns, each giving one of the required 
colors, the image may be thrown, superposed, upon 
a screen, the combination giving a colored represen- 
tation of the photographed object ; or the three records 
may be directly superposed. The latter is the basis of 
three-color printing, as we have seen. 

The combining of three negatives by means of an 
optical lantern — thus obtaining views in natural colors 
— is an important branch of color photography, though 
its practice is attended with considerable difficulty, 
especially in the matter of matching the plates to secure 
the right effect when combined. The whole process, 
however, has recently been simplified to a considera- 
ble extent by a French scientist, M. Andre Cheron. 
He has devised a three-lens camera which takes the 
three views (one with each color screen) upon a single 
plate and at one operation. But the ingenious thing 
about M. Cheron' s apparatus is that it serves as the 
lantern as well. A lantern transparency is made from 
the negatives and this is placed in the camera in the 
portion occupied by the original photographic plate. A 
lamp, Welsbach burner, or any good light serves to pro- 
ject the three images, and these pass through a large 
condensing lens placed in front of the camera lenses, 
thereby superposing the images upon the screen. 

But all the while that the three-image process of 
[240] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

color photography was being developed, efforts were 
made to obtain a satisfactory method which would do 
away with the necessity for these separate negatives 
and the consequent optical lantern. 

" Forty years ago Ducos du Hauron suggested the 
production of a screen-plate as forming a simple method 
of color photography, which consists of a sheet of trans- 
parent paper mechanically covered upon its surface 
with three kinds of colored stripes or divisions. Writ- 
ing of this method Du Hauron said: 'Let us imagine 
that one covers the surface of the paper on the side 
where the color stripes are imprinted with a prepara- 
tion which gives, directly under the influence of light, 
a positive proof, and that one receives on its reverse 
side — namely on the side not covered with stripes — 
the image of the camera. It will happen that the 
three single colors will filter through the paper and form 
each its positive print, that is, its print in light of the 
corresponding ray of color, and the three prints 
will be formed with the same rapidity, in spite of the 
unequal degrees of actinism of the three simple colors, 
if one has been careful to give each of these three sorts 
of stripes a relative translucency, inversely as to 
photogenic power of these same colors on the prepa- 
ration employed. '" 

It is obvious that the colors must be distributed over 
the proposed surface in quantities so minute that 
when viewed by the eye they would be merged together 
just as are the details of an engraving. Du Hauron 
made his suggestion in 1868, but it was not until 1895 
that the first screen-plate process was put forward 

VOL. VIII. — 16 [ 241 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

commercially. The credit for this belongs to Dr. 
Robert Joly, of Dublin, although Mr. J. W. Mc- 
Donough in America produced a practical screen- 
plate about the same time. 

On Joly's plates "the three colors were arranged 
regularly in lines, and were applied to the glass by 
means of a ruling-pen Joly used two color- 
screens — a ' taking screen' that was fixed in front of the 
plate while the exposure was being made, and a ' view- 
ing screen' which was put in front of the positive for 
viewing the picture, and might be bound up with it 
as a fixture, if preferred." 

By the use of ruling-machines, lines so fine that 
forty could be put in a millimeter (more than a thou- 
sand to the inch) were obtained, but even with these 
it was not felt that the desired degree of tenuousness 
had been reached. 

Several other methods of making line color-screens 
have been devised, of which two, perhaps, are worthy 
of attention. One is the recent invention of Robert 
Krayne. "Sheets of celluloid are stained in the requi- 
site colors and are then placed on the top of each other 
and cemented together so as to form a continuous 
block of red, green, and blue celluloid. A section is 
then cut straight through this block, and a leaf ob- 
tained which shows through its width the red, green, and 
blue lines which were originally the leaves forming the 
block. To make the Krayne mosaic screen these 
lined screens are again cemented together to form a 
block, and a section is now cut at right-angles to the 
line direction.' ' 

[242] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

Mr. John W. Powrie in his color-screen has also 
discarded ruling methods. He takes advantage of the 
well-known hardening and protective property of 
bichromate of potassium when exposed to light, to 
stain a coated glass plate in lines of red, green, and 
blue, one color after another. These lines are only 
1/600 of an inch in thickness, and more than twice 
as fine as those that can be obtained by ruling-machines. 

But the popularity of these geometrically made color- 
screens (they are made in hexagonal and square patches, 
as well as in lines) has been somewhat impaired by the 
appearance of the " random grain" plates recently 
invented by Messrs. Auguste and Louis Lumiere, 
of Lyons, France. It is true that this idea is of some- 
what earlier origin, for in the last decade of the nine- 
teenth century, J. W. McDonough prepared plates 
by scattering small flakes of colored shellac over the 
surface and then fusing them, but he soon abandoned 
this line of experiment for what he considered the 
greater advantage of the ruled screen. The Lumiere 
"autochrome" plate is made by placing on the glass a 
layer of minute grains of potato- starch colored red- 
orange, green, and violet, so thoroughly mixed that 
they present a neutral gray to the eye. The grains are 
so small that five and a half million will go on a square 
inch of surface, and any spaces between them through 
which white light might filter are filled up with a black 
carbon powder. This layer is rolled and pressed on 
the glass, to which an adhesive coating has previously 
been applied. The layer of colored grains then re- 
ceives a coating of waterproof varnish and on this is 

[243] 



SCIENCE IN THE INDUSTRIAL WORLD 

spread a gelatine-bromide emulsion sensitive to all 
colors. Thus we have a complete outfit — photo- 
graphic plate and color screen in one. In exposing 
this plate in the camera the glass side is placed towards 
the lens, and the light consequently has to pass through 
the granular colored layer before reaching the gelatine 
film. The resulting negative is developed but not 
fixed, and the reduced silver is dissolved by means of 
the acid permanganate of potassium process. The 
plate is then transformed from a negative to a posi- 
tive, and each colored particle lets the light pass which 
is necessary to produce that special shade. When held 
up to the light the plate shows the color as well as the 
shape of the photographic subject. 

The ease of manipulation and excellent results of 
the Lumiere autochrome plates have turned inventive 
effort largely to the methods used in their manufacture. 
Already a new plate known as the "omnicolor" has 
been produced. This, however, goes back to the old 
idea of the geometrical plate and is prepared by "treat- 
ing a gelatine film (upon a glass plate) successively 
with certain reserves, coloring matters, and varnishes, 
thus producing a kind of mosaic of red and green 
rectangles, and blue lines. The red and green fields 
are quite regular in form ; the blue lines, on the other 
hand, show constrictions at constant intervals, cor- 
responding to their intersections with the red fields. 
As a matter of fact this red color is distributed in nar- 
row red bands, and the blue lines superposed upon 
these produce at the point of contact a purplish violet 
color." These plates are used precisely as the auto- 

[244] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

chromes, although the colors differ appreciably. "the 
green tending more toward yellow and the blue being 
less violet." 

The great drawback to the autochrome plate is the 
loss of light. This defect is necessarily present wher- 
ever a color screen of any description is used, but the 
sensitiveness of the autochrome plate is comparatively 
small owing to the imperfectly transparent nature of 
the starch grains as well as the black filling-in material 
of the unavoidable interstices. Therefore, the physi- 
cist is still laboring to obtain increased brilliancy and 
brightness in the picture. 

With this end in view Mr. Jan Szczepanik, by taking 
advantage of the property possessed by certain sub- 
stances of absorbing coloring matter from others, has 
recently produced a plate that possibly may show the 
way to a considerable advance in indirect color pho- 
tography. 

" Szczepanik prepares three solutions of gelatine 
or gum-arabic. Each solution is colored with a suitable 
dye, and is then evaporated to dryness. The particu- 
lar dyes used must, of course, have a preference for 
collodion. The solid masses of gelatine or gum- 
arabic obtained by evaporating the solutions are finely 
powdered, and the three powders of different colors 
are carefully mixed. The mixture of these colored 
powders is then sifted over a slightly moist collodion 
plate by means of a special apparatus. The coloring 
matters migrate from the gelatine powder into the 
collodion film, producing a mosaic of small colored 
patches similar to the starch granules of the autochrome 

[245] 



SCIENCE IN THE INDUSTRIAL WORLD 

plate. The powder originally dusted on the plate, 
which has lost its color, is washed off." 

Results in color photography have also been obtained 
by the use of prisms or diffraction gratings instead of 
dyes or pigments. Professor Lippmann, of Paris, 
whose direct "interference" process we noted above, 
has devised a method employing the minute spectra 
of prisms. The apparatus employed is similar to the 
photographic spectroscope, except that "the single 
slit of the spectroscope is replaced by a series of slits 
very close together consisting of fine transparent lines 
ruled five to the millimeter. This grating is fixed at 
one end of a solidly built box, the other end carrying the 
photographic plate, and between these is a converging 
lens, in front of which is a prism of very small angle. 
The object to be reproduced is projected on the grat- 
ing, illuminated with white light. The light passing 
through the prism and lens falls on the sensitive plate, 
producing a negative in black and white which under 
the lens appears lined, each line divided into small 
zones, which are parts of an elementary spectrum. 
If the negative be now replaced in its original position 
and illuminated by white light, the image of the object 
photographed is seen in colors which are complemen- 
tary to those of the object; the latter appears in its 
own proper colors when the negative is replaced by 
a positive." 

It will be seen that the apparatus in which the ex- 
posure was made must also be used to get a color image 
of the photographed subject. M. Andre Charon, of 
Paris, has more recently improved the process to some 

[246 J 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

extent, but nevertheless, like all of its type, it does 
not lend itself to practical work, and will always remain 
of more use and interest to the physicist than to the 
photographer. 

THE FUTURE OF COLOR PHOTOGRAPHY 

We have seen that the screen-plate, and especially that 
form developed along the line which has produced the 
autochrome and kindred plates, has thus far given 
the most satisfactory results in color photography. 
Nevertheless, the practicality of these methods is not 
very pronounced, and the popular attitude toward 
them was ably expressed by Doctor Mees in his recent 
address before the London Society of Arts. 

"With regard to the whole use of screen-plates, 
one is bound to feel that, interesting as they are, at 
the present time their use must be limited. No color 
process which cannot be printed on paper can hope 
to appeal to the great mass of workers. . . . What 
screen-plates need, in fact, as their complement, is a 
printing-process such as some improved bleaching- 
out emulsion, which could be placed on paper and on 
which the plates could be printed. " 

In these words the future of color photography is 
clearly outlined, and before dismissing the subject it re- 
mains to note what is being done in this direction. 

"There is a method," says Chapman Jones, "that 
has been in the minds of those interested in these mat- 
ters for nearly thirty years, and latterly more or less 
worked upon by many investigators with more or less, 

[247] 



SCIENCE IN THE INDUSTRIAL WORLD 

but on the whole gradually growing, success. The 
three necessary colors are put on the paper to begin 
with, and the light destroys or bleaches those that are 
not wanted. The method depends upon the fact 
that light can affect a substance only when it is ab- 
sorbed, and therefore when a mixture of unstable col- 
ored substances is exposed to colored light, there is 
always a tendency for those substances that are of the 
same color as the light to survive the longest because 
they reflect more of the light than the others. " In 1907, 
such a paper ready for exposure under the color plate 
was actually prepared. "The colors are made more 
sensitive by the addition of anethole, and after exposure 
the print is soaked in benzine or acetone to remove 
the sensitizer. This paper gives surprisingly vivid 
reproductions of the color of the original, but the 
prints are not very stable to light." 

When some means of making stable prints on such 
a paper is found, color photography will probably 
have reached its highest state of development, for, as 
we have seen, the photography of color is something 
the scientist as yet sees no possible way of accom- 
plishing. 

CHRONO-PHOTOGRAPHY— -MOVING PICTURES 

A means of representing motion, which has reached 
its highest development in the well-known and popular 
moving-picture machines of the present day, was de- 
vised long before the photographic plate came into 
general use. As early as 1833, M. Plateau, a Belgian 

[248] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

scientist, invented an instrument which he termed 
the phenakistoscope, and by which he demonstrated 
the principle of the persistence of vision; that is, the 
retention of an illuminated image in the retina after such 
illumination has been quenched. From this instru- 
ment was subsequently developed the zoetrope or 
"wheel of life" — a toy which many readers will doubt- 
less remember. It consisted of a hollow cylinder 
revolving on a pivot and having a band of short, per- 
pendicular slits, close together, perforated in its cir- 
cumference. If a strip of pictures of the same object 
in different positions were placed around the inner 
surface of the cylinder, and the instrument rapidly 
revolved, the effect of the series of pictures, passing 
in succession in front of an eye placed on a line with the 
row of slits, was that of the pictured objects performing 
some sort of motion, as a horse running, a bird flying, 
or a human being dancing. 

No further interest seems to have been taken in the 
matter until after 1870 when a Frenchman, Raynaud 
by name, modified and improved the zoetrope by re- 
flecting the succession of images in a many-sided mir- 
ror placed within the cylinder. This instrument, which 
Raynaud called the praxinoscope, gave precisely the 
same effect as the zoetrope. It must be understood 
that the pictures used in these toy instruments were 
not photographs but a series of colored reproductions 
of drawings, and consequently, while this whole matter 
does not come under the head of chrono- or animated 
photography proper, some account of it in the history 
of the pictorial representation of motion is necessary. 

[ 249 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

In the 70's or 80' s of the last century three scien- 
tists, Edward Muybridge in America, Stephen Marey 
in France, and Anschiitz in Germany, although pur- 
suing an entirely different subject, took the first steps 
in the development of chrono-photography. These 
men were deeply engrossed in the study of animal 
locomotion, and Muybridge's hobby was the horse. 
In 1877 he placed a series of cameras at regular intervals 
opposite an inclined white reflecting surface. A fine 
thread was stretched from the shutter of each camera 
and in front of the row a horse was caused to pass. 
The animal naturally broke the threads in turn, and 
as these acts operated the shutters, the investigator 
obtained a series of plates showing the horse's atti- 
tude at the moment of exposure. To combine these 
plates and obtain a moving picture Muybridge devised 
an apparatus which he termed the zoopraxiscope, by 
which the positives, arranged on an immense revolv- 
ing disk, were brought one after another in rapid suc- 
cession into the light of a projecting lantern. 

Marey took up the principle of the "photographic 
revolver" which Jansen had invented in 1874 and 
adapted it to the analyses of very rapid movement. 
By means of the photographic gun he obtained ex- 
cellent and valuable photographs of birds in full flight. 
Mention should also be made here of the work of George 
Demeny, a pupil of Marey' s, who devised the photo- 
scope for reproducing the motion of a man's lips so that 
deaf mutes could read "photographed sentences." 

Anschiitz' s contribution to chrono-photography was 
the tachyscope (1887). His sensitive plate was a large 

[250] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

glass disk on the periphery of which positives were 
made. The disk was fitted with contact pins and was 
rotated behind a slight opening, each picture, when it 
came behind the opening, being illuminated by a spark 
from a vacuum tube. 

Such, in brief, is the story of the development of 
animated photography up to the time when a very 
important invention revolutionized this, as well as 
every other, branch of photographic art. As the reader 
may have guessed, the flexible celluloid film, substi- 
tute for the glass plate, is referred to. Marey now 
employed a long roll of sensitive film fed behind, and 
in the focus of, a photographic lens, and the same 
contrivance was quickly adopted by Thomas A. Edi- 
son in his kinetoscope. Edison is said to have con- 
ceived the idea of the kinetoscope as early as 1887. 
He at first proposed fixing the series of impressions on 
the outer rim of a disk as in the case of the t achy scope, 
but the tremendous advantage of the flexible film 
caused him to abandon his first principle. The kinet- 
oscope, patented in 1891, was quickly followed by 
many other similar moving-picture machines with 
which the public is familiar under various names — 
vitascope, vitagraph, biograph, phantoscope, kine- 
matograph, etc. The last-named appeared in 1895, 
and since that time no radical improvement has 
been made in moving-picture machines, although 
their use and popularity have enormously increased. 

The method of making moving pictures is compara- 
tively simple in principle, although in matters of ad- 
justment and other practical details the greatest care 

[251] 



SCIENCE IN THE INDUSTRIAL WORLD 

and nicety must be used. At a high speed the film 
is fed rapidly behind the camera lens, the shutter of 
which is operated by a small motor. The speed of 
the shutter is such that from 900 to 1,800 separate pic- 
tures must be taken every minute, or from fifteen to 
thirty a second. Thus when any scene — a procession 
or a dramatic performance — progresses in front of 
the camera, a record will be obtained of the relative 
position of objects in the camera field, say every one- 
fifteenth of a second. 

The films used are either if or 2 f inches in width, 
and their length about fifty-five feet. Of course in 
many instances a number of films have to be used to 
reproduce a scene. Thus in the animated represen- 
tation of a recent pugilistic encounter, which the whole 
world was believed to be passionately longing to view, 
the camera was operated steadily for one hour and 
forty minutes, and in this time between six and seven 
miles of celluloid film passed behind the winking lens. 

To reproduce the pictures, a positive strip is printed 
directly from the developed negative, and this is passed 
through the kinematograph, biograph, or other mov- 
ing-picture machine in the same manner as the original 
film is fed into the camera — a rapid shutter exposing 
the consecutive positions of the scene at the same 
intervals as were used in photographing the original. 

The question will naturally be asked: What makes 
the picture "move"? And in answering this it must 
be first explained that the human eye is an absolutely 
essential part of any chrono-photographic apparatus. 
Let us take, for instance, the case of the kinemato- 

[252] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

graph and consider what happens. In this particular 
moving-picture machine photographs are taken at 
intervals of one-fifteenth of a second. 

Owing to the property of the retina, called " per- 
sistence of vision, " to which we have referred above, 
a luminous impression cannot be instantly removed 
but will persist, and hence affect the optic nerve, for 
2/45 of a second, and be further prolonged, though 
gradually weakening, for 2/45 of a second longer, 
after the illuminated object has suddenly disappeared. 
Now the moving pictures have been taken at 1/15 or 
3/45 second intervals, and the various pictures are 
exactly alike in so far as the stationary part of the scene 
is concerned. A picture (let us call it image No. 1) is 
thrown on the screen and the opaque screen or shutter 
of the machine then masks the light for 1/45 of a 
second. Therefore, owing to the persistence of the 
image, we shall see the picture not only during the 
1/45 second of eclipse but also 1/45 second afterward. 
But during the time of eclipse the next picture in the 
film (No. 2) has been substituted for No. 1, and con- 
sequently when the light is again unmasked after the 
1/45 second interval we shall see not only the image 
No. 1, somewhat weaker, though still distinct, and super- 
posed on it is image No. 2. Since the stationary parts 
coincide exactly, the eye perceives the sensation of the 
moving object, the attitudes and positions in No. 1 being 
succeeded by those of No. 2, and so until nine hundred 
such impressions are made on the retina every minute. 

There is another method of presenting moving 
pictures, in use in the familiar slot-machine, or muto- 

[253] 



SCIENCE IN THE INDUSTRIAL WORLD 

scope, as it is called. Instead of the continuous film, the 
pictures are arranged in reels and brought into a verti- 
cal position before the eye. The reel is made up of 
several hundred photographs in consecutive order, and 
between each one is placed a piece of thin, calendered 
cardboard such as playing-cards are made from. 
These act in the manner of a spring to throw the photo- 
graphs one after the other rapidly past the viewing 
lens. The insertion of the coin starts the motor which 
operates the reel. 

Moving picture presentations are of two classes, 
the first, in which pageants, processions, races, or any 
other progressive events, are reproduced; and in the 
second, dramatic performances are depicted. In the 
latter, some startling and almost miraculous happenings 
are usually introduced, to the admiration and de- 
lighted applause of the spectators. These effects are 
accomplished by what is known as the " pause," that 
is, the camera is run up to a certain point, stopped, the 
mise-en-scene changed, and the picture-taking con- 
tinued. Thus in the familiar "automobile accident/ ' 
the camera is operated until the automobile is right 
upon the prostrate victim. Then a legless cripple, 
made up like the original model, and some artificial 
legs, are placed in the scene and the action continues. 
The legless man is then shown moving the dismembered 
limbs in the air. Now the legs are seen to fly back to 
the trunk, and at length the original model walks away, 
none the worse for his experience. These different 
phases of the thrilling episode take much time and 
trouble to prepare, during which time the camera is 

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PHOTOGRAPHY, SCIENTIFIC ASPECTS 

"in pause"; but when thrown on the screen in the 
moving-picture theatre the whole thing is over in the 
fraction of a minute. 



THE USES OF PHOTOGRAPHY 

It is safe to say that to-day there is no field of scien- 
tific research, or the practical conduct of affairs, to which 
photography has not become an indispensable adjunct. 

Of the immeasurable realms of space, as well as 
the minute, invisible world about us, the photographic 
plate has given knowledge that never could have been 
obtained by the human eye alone. It has unfolded 
the wonderful world of the spiral nebulae and laid the 
groundwork for modern conceptions of the universe. 
It has shed light on the nature of the streaky nebulae 
and their connection with the great star-stream of the 
Milky Way, into whose depths it has given us the only 
means of penetration. It has shown the existence of 
countless stars, as well as faint members of the solar 
system, which the human eye aided by the telescope 
lens has been unable to perceive. It has given much 
additional insight into the conditions and development 
of the sun's constituents, and enabled us to measure 
the motion of the stars toward and away from our 
own solar system. 

It would be impossible to give any account of the 
recent triumphs of physical and chemical research 
without allotting considerable space to the part the 
camera has played in them. The fact that the sun 
and fixed stars contain the same elements as does the 

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SCIENCE IN THE INDUSTRIAL WORLD 

earth is imperishably recorded by spectrum photog- 
raphy. All knowledge revealed by the ultra-violet 
rays of the spectrum has been acquired by use of the 
photographic plate, since the extremely short length 
of the waves renders them invisible to the human eye. 

The value and use in medicine and surgery of pho- 
tographs taken with the Rontgen ray, have already 
been described. More recently the kinematograph 
has been adopted in the study of diseases, especially 
those of nervous origin. By its means faithful records 
of the abnormal play of features, convulsive move- 
ments, strange attitudes, faulty gait, etc., may be 
obtained, the careful observation and study of which 
when thrown on the screen has proved of invaluable 
aid and service to the physician. The mystery of the 
background of the eye was finally solved by stereo- 
photography. The use of microphotography in obtain- 
ing records of minute organisms and their development 
is only another of the many ways in which photog- 
raphy has become indispensable to the pathologist. 

In zoology and botany the camera has revolution- 
ized all methods of observation and research. The 
photography of animals and plants in their natural 
environment is a most valuable means of investiga- 
tion and information and not of mere illustration, as 
some may suppose. For these same purposes the kine- 
matograph is being put more and more to practical 
use by the zoologist. Microphotography is rarely 
absent from the work of the botanist, and from it 
results of enormous practical and economic value have 
been obtained in the department of plant pathology. 

[256] 



PHOTOGRAPHY, SCIENTIFIC ASPECTS 

In architecture, surveying, and map-making, the 
camera has been put to much practical use. It is 
fast replacing — especially in mountainous countries — 
the plane-table as a means of obtaining accurate topo- 
graphical maps. Architectural measurements are 
obtained with great exactness from photographs. 

Into the conduct of law, photography now enters 
in large part. Its applications are too numerous to 
be mentioned here in detail, but its possibilities as 
a means of information will be evident to anyone who 
thinks a moment on the subject. The establishment 
of identifications — one of the most difficult matters in 
criminal procedure; the detection of forgeries by pho- 
tographic enlargements; the accumulation of indis- 
putable descriptive evidence in all kinds of accidents; 
the preservation of the exact conditions surrounding 
the commission of crime, which may afterwards be 
changed, such as the appearance of wounds, the loca- 
tion of hand and foot prints; the relative position of 
furniture, etc.; the collection and dissemination of 
criminals' portraits — these are but a few of the ways 
in which photography is employed by every well- 
policed nation. Truly may it be said that in every 
department of human activity "the sun brings all 
things to light." 

VOL. VIII. — 17 



[257] 



XI 

PAINTS, DYES, AND VARNISHES 

ANY liquid substance that is applied to the 
surface of a solid, either as a protective or for 
decorative purposes, may be regarded as a 
" paint,' ' generally speaking. But when used in this 
way the word is far too comprehensive. Subdivision 
and classification of the substances used for coloring 
is necessary for intelligent understanding of the subject. 
Fortunately the substances all fall naturally into three 
or four definite groups, determined either by their use or 
by their chemical nature, although the dividing line is 
not clearly drawn in some instances. 

For practical purposes the substances generally known 
as pigments may be considered either as paints, var- 
nishes, stains, or dyes. The last two are identical in 
many instances, the substance upon which their appli- 
cation is made, and the method of applying them, de- 
termining whether they shall be called "stains" or 
"dyes." Thus we speak of " staining" a piece of wood, 
and of "dyeing" a cotton or wool fabric, although the 
pigment used in each instance may be the same. 

Generally speaking, dyes, stains, and varnishes are 
transparent or translucent substances in solution, or 
chemical combination, with a liquid; while paints are 
opaque, insoluble substances, held in suspension in 

[258] 



PAINTS, DYES, AND VARNISHES 

some medium. Thus a stain or dye enters into intimate 
combination with the wood or the fabric to which it is 
applied. Being transparent it does not conceal the 
grain of the wood or the fibers of the cloth that it 
colors, and does not increase its thickness to any ap- 
preciable depth. A paint, on the other hand, simply 
covers and conceals the underlying structure by an 
appreciable layer without becoming an integral part of 
it. This is shown in the familiar example of paint 
peeling off wood, leaving the original surface exposed. 

A varnish is essentially a transparent paint, rather 
than a stain. Color effects may be produced very much 
the same as in the case of stains by incorporating a 
transparent pigment in the varnish; but it is possible for 
a varnish to peel off from an underlying surface, just as 
in the case of a paint. 

In speaking of the various paints their "covering 
power" will often be referred to. This should be under- 
stood as meaning the amount of surface that a pigment 
will conceal with an opaque layer. This quality is often 
determined by the size of the individual particles of the 
opaque pigment, the smaller the particles the greater 
the covering power, generally speaking, — a rule, how- 
ever, that is subject to many exceptions. 

The processes in paint manufacture known as 
" grinding," "filtering," " precipitating," etc., are suf- 
ficiently self-explanatory without going into details 
here. What is known as "levigation," however, needs 
fuller explanation. 

The principle of the process of levigation depends 
upon the fact that the larger particles of a substance, or 

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SCIENCE IN THE INDUSTRIAL WORLD 

heavier particles when mixed with lighter ones, tend 
to settle first to the bottom when the substance is agi- 
tated in water and then allowed to stand. In practice 
there are various methods of applying this principle. 
A very common one, in use where the raw material is 
composed of a mixture of several different-sized particles, 
is to arrange currents of water and settling-tanks so as 
to separate these particles into deposits of great uni- 
formity. In an arrangement of a series of tanks through 
which the liquid flows, the first tank will arrest and 
collect the coarser particles; the second tank will arrest 
the particles that are somewhat finer; the third will 
arrest still finer particles, and so on until the last tank 
receives only the very finest particles. This may be 
taken as a typical method of levigation. And without 
entering into details it may be said at once that this 
process is perhaps the most important single one con- 
nected with mineral-pigment manufacture. 

Reducing the pigment to a fine powder by grinding is 
as old as recorded civilization itself. The kinds of mills 
used for grinding do not differ, except in details, from 
those used at various times for grinding other materials, 
such as grain. Indeed, the mortar and pestle, quern 
or hand-mill, millstones of various kinds, and, finally, 
roller-mills, have been applied to color-grinding in 
the order of their development, just as in the case of 
grinding grain. 

Only second in importance to the pigments themselves 
— if, indeed, their place may be considered secondary 
— are the vehicles in which they are incorporated for 
use in painting. Water is, of course, an important 

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PAINTS, DYES, AND VARNISHES 

vehicle. But much more important are the "drying- 
oils." Of these drying-oils linseed oil is of most import- 
ance to the painter — more important, in fact, than all 
the other vehicles combined. 

By a "drying- oil" we mean one that, when exposed 
to the atmosphere, forms a thin, tough film, insoluble 
in water, and not acted upon readily by any chemicals 
that are likely to come in contact with it. The number 
of such oils is very small in comparison with the num- 
ber of oily substances, of which olive oil may be taken 
as a typical example of a non-drying oil. A thin film 
of this oil spread upon a surface of glass, let us say, does 
not tend to form a hard film and lose its peculiar oily 
quality, even after weeks of exposure to the atmosphere ; 
whereas under similar conditions a film of linseed oil 
would be converted into a hard, impervious layer, in 
a matter of twenty- four hours. Olive oil, therefore, and 
all the other non-drying oils, are useless as paint 
vehicles. 

For special purposes several other drying-substances 
besides the oils are used for pigment vehicles, among the 
most used of these being turpentine, benzoline, shale 
spirits, benzole, coal-tar naphtha, wood alcohol, alcohol, 
and water. But all of these must be regarded as strictly 
of secondary importance to the drying-oils, although 
for special purposes they are indispensable. 

Of the drying-oils there are, besides linseed oil, 
poppy-seed oil, firseed oil, weld-seed oil, hempseed oil, 
tobacco-seed oil, menhaden oil, walnut oil, and Chinese 
wood oil. But all these together play a very insignificant 
part as paint vehicles in comparison with linseed oil, 

[261] 



SCIENCE IN THE INDUSTRIAL WORLD 

which can be produced in great quantities and at a cost 
that is a mere fraction of that of any of the others. 

Linseed oil is the product of the seed of the flax 
plant, Linum usitatissimum^ which is grown abundantly 
in every grain-raising region of the world outside the 
tropics. It is a little seed, flat oval in shape, lustrous, 
and of a pale-brown color. The oil is obtained from 
the seed by a process of pressing, after the seed has 
been subjected to a series of preparatory processes. 

As a vehicle for pigments it is marketed in two forms, 
known respectively as "raw" and "boiled" oil. The 
raw linseed oil is the product obtained from the seed 
by pressure, without further treatment — or at most a 
process of clarifying and refining — and represents 
the oil practically in a state of nature as it exists in the 
seed. The boiled oil, as the name suggests, is the natural 
oil which has been heated above the boiling point (about 
500 F.) and to which is added a small quantity of some 
substance known as a "drier." The boiling and the 
addition of the drier change the chemical composition of 
the oil slightly, and give it somewhat different proper- 
ties from the raw oil — mostly in the matter of increas- 
ing its rapidity in drying. For this reason it is a favorite 
vehicle for many kinds of painting where a hard, tough, 
lustrous coat that dries quickly, is desired. This coat 
is somewhat more prone to crack than the one formed 
by raw linseed oil, but this tendency may be corrected 
by adding a little raw oil to the mixture, the compound 
forming the ideal vehicle for most commercial painting. 

The quantity of drier added to the boiling oil is very 
small, usually four or five pounds to the ton of oil. 

[ 262 ] j 



PAINTS, DYES, AND VARNISHES 

Larger quantities of driers impair the lasting qualities 
of a paint, and should not be used except in places where 
the rapid drying of a layer of paint is of more importance 
than its durability. 

Some vehicles, such as turpentine, act as rapid driers, 
but are not considered as "driers" in the generally ac- 
cepted commercial use of the term, which applies to 
such substances as red lead, monoxide of lead, the acetate 
or borate of lead, one of the manganese salts, or one 
of several zinc or iron salts. These may be used 
separately or in various combinations, and are the basis 
of the numerous " patent driers" on the market, the 
indiscriminate use of which has brought such sub- 
stances into disrepute. 

While linseed oil is a relatively cheap substance as 
compared with other drying and non-drying vegetable 
oils, its cost is sufficient to lead to much adulteration 
and to stimulate the search for cheaper substitutes. 
None of these substitutes equals linseed oil, however, 
although some mixtures of boiled oil, resin oil, and resin 
or turpentine, are fairly good vehicles. 

Hempseed oil, while scarcely attaining the position 
of a rival of linseed oil as a vehicle, is used extensively 
in Russia where hemp is grown on a large scale. In 
that country hempseed and linseed are usually mixed 
together, so that the expressed oil is a mixture of linseed 
and hempseed oil. As hempseed oil seems to possess 
all the good qualities of linseed oil, the mixture is a high- 
class paint-vehicle. In this country the cost of hempseed 
oil for commercial painting is prohibitive. 

Poppy-seed oil has the advantage over linseed oil 



SCIENCE IN THE INDUSTRIAL WORLD 

of being almost colorless. For this reason it is a favorite 
with artists; but it is far too expensive for use in com- 
mercial paints. This is true also of walnut oil and tung, 
or Chinese wood oil. 

Turpentine, which is a product of the distillation of 
the resin of pine trees, is a most useful paint-vehicle 
for certain purposes. It volatilizes rapidly on exposure 
in thin layers to the air, but leaves behind a thin layer 
of resinous substance that acts as a binding medium 
for the particles of pigment. It mixes with alcohol, 
ether, and benzine, and is a good solvent of fats, oils, 
and resins, so that it can be used with almost every kind 
of paint or varnish. It dries very quickly, and for quick- 
drying paints, stains, and varnishes is indispensable to 
the painter. 

The best substitute for turpentine, although inferior 
as a paint-vehicle, is resin spirit, the product of the 
distillation of resin. In its most refined forms it can be 
used as a substitute for turpentine for every purpose; 
but it has a very offensive odor, and its use is largely 
confined to making cheap varnishes. 

The two alcohols, methyl alcohol and ethyl alcohol, 
are used extensively as vehicles in the manufacture of 
varnishes and enamel paints. They are good solvents of 
gums and certain resins. They evaporate rapidly and 
as vehicles for pigments constitute quick-drying 
"paints." The most familiar example of one of these 
is the ordinary commercial shellac varnish. 

Besides the vehicles we have mentioned there are, of 
course, scores of others, either " patent" or " proprie- 
tary" mixtures, which are constantly appearing on the 

[264] 



PAINTS, DYES, AND VARNISHES 

market. Most of them are mixtures, but their exact 
compositions are trade secrets, and need not be consid- 
ered here. 



THE PIGMENTS OF ANTIQUITY 

"When Noah built the ark," says a writer, "and 
coated the seams with pitch, he was doubtless following 
the most approved system in use of protective coatings 
on structural materials, which was then probably of 
remote antiquity and traditional origin, and which he 
may have learned when he was a boy four or five hun- 
dred years before." 

It appears, then, that the use of some sort of protec- 
tive in the form of paint or varnish dates back to a very 
remote period of antiquity, not necessarily on the state- 
ment of the Mosaic writers alone, but from existing 
evidences that antedate them by many centuries. It is 
interesting, however, that one of the earliest written ac- 
counts of boat-building shows that the workmen coated 
their boats with the same material that is still used for 
similar purposes the world over. Since it is unlikely that 
this ideal material should have been hit upon from the 
very first, it is evident that the use of protectives had 
passed through a long experimental stage at the very 
dawn of written history. But even if no word had ever 
been written about this, we still have the mute evidences 
in the form of remains from ancient dwellers of the Nile 
and the Euphrates, showing that paints, varnishes, and 
dyes were used extensively by them for ornament and 
decoration as well as for protectives. 

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SCIENCE IN THE INDUSTRIAL WORLD 

We shall see a little later that within the last half- 
century a complete revolution in the method of making 
certain colors has taken place, thanks to the science of 
chemistry. Yet the basis of most paints is still the time- 
honored white lead — a substance known to the ancients, 
and used by them practically as it is used to-day. We 
know that as early as the fourth century B.C., there were 
written accounts of the process of making this substance, 
which seemingly differed very little from the process 
in use in some countries to-day. 

Varnishes seem to have been used at a date almost, 
if not quite, as early as that of paints. The peculiar 
coatings of the Egyptian mummy-cases has been ana- 
lyzed and found to be a solution of resin in an essential 
oil, such as turpentine or oil of cedar, and therefore 
practically identical with the ordinary varnishes of 
to-day. The revolution in the art of paint- and pigment- 
making, therefore, lies outside the field of the exact 
knowledge of the chemical nature of such basic sub- 
stances as resin, pitch, and white lead. There have 
been revolutionary changes in the methods of obtaining 
and using these substances, of course, but the great 
revolution has come in the manufacture of the colored 
pigments along the lines of synthetic chemistry. The 
ancient pigment-maker was largely dependent upon the 
substances furnished him by Nature in a form ready for 
use. Many of these were rare, costly, and difficult to 
manipulate. His modern successor, with his knowl- 
edge of chemical elements and reactions, produces the 
same material in his laboratory, at a mere fraction of 
their former cost, and from substances that would 

[266] 



PAINTS, DYES, AND VARNISHES 

never have been dreamed of in earlier times. An ex- 
ample of this is the manufacture of ultramarine. 
The early painters made this substance by grinding 
to powder the gem "lapis lazuli," and the pigment so 
produced was worth many times its weight in gold. The 
pigment-maker of to-day produces a deeper and better 
color by a chemical process in which sulphur, soda, 
silica, and clay are the important factors, and makes a 
handsome profit if his product brings him fifty cents 
per pound. This is but one example of how a product of 
man's puny laboratories has supplanted that of Nature's 
great one. We shall see presently how many such ex- 
amples there are in this particular field. 

BLACK PIGMENTS 

The element carbon, in one or another of its varied 
forms, is the basis of practically all black pigments. It 
is one of the most universal elements, and being found 
in abundance in the mineral, vegetable, and animal 
worlds, pigments are made of it from all three of these 
sources. Although all forms of carbon, such as dia- 
mond, coal, charcoal, and lampblack, are identical chem- 
ically, it is obvious that only certain of these forms are 
available for making black pigments. Thus diamond 
dust is white and coal dust black; yet both are pure 
carbon. The chemist would explain, however, that 
both their substances are crystalline, and that only the 
non-crystalline forms of carbon give the desired pure- 
black color. Of much greater importance to the pig- 
ment-maker are such plebeian substances as wood, 

[ 2 6 7 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

charcoal, bones, and smoky lamps charged with foul- 
smelling oils, as it is from these sources that he makes his 
wares. 

As most of the forms of carbon found in the mineral 
world, except the mineral oils, are crystalline in char- 
acter and hence not available for making the best pig- 
ments, the vegetable kingdom furnishes the cheapest 
sources. For production from the latter two general 
methods are used; one, the process of dry distillation, 
or heating the substance to be carbonized in the absence 
of air; in the other the supply of air is restricted. An 
example of the last method is shown in the soot formed 
by smoky lamps or defective gas-burners, such soot 
making the finest forms of black pigment which may be 
used without further treatment. In the case of the car- 
bon produced by dry distillation, a good pigment can 
be produced only by grinding and the addition of oil. 

In the commercial world there are two principal 
kinds of black pigments, " charcoal' ' blacks and 
"soot" blacks. Practically all black pigments on the 
market, regardless of their commercial or trade names, 
have one or the other of these two blacks in them. It 
is possible, of course, to make a fine black from such a 
substance as ivory; and "ivory black" was formerly 
made exclusively from this substance. But aside from 
some of the very finest forms of artists' pigments, little 
ivory black is now made from ivory, the name indicating 
the quality rather than the composition of the pigment. 

In making charcoal black the first step in the process, 
that of making the charcoal, does not differ materially 
from that of the ordinary process of charcoal-burning. 

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PAINTS, DYES, AND VARNISHES 

There is a difference in the selection of woods from 
which the charcoal is made, however, the soft woods 
making much better pigments than the hard. Spent 
tan-bark makes a good pigment charcoal, and is used 
extensively for this purpose in some places. 

The usual method of burning the charcoal is to pile 
short pieces of wood on end into a stack resembling a 
cock of hay, some of these stacks containing several cords 
of wood. When completed, the stack is covered with a 
layer of clay or dirt, a certain number of openings being 
left for the admission of air. The wood is then lighted, 
and allowed to char by slow combustion, the rate of 
burning being regulated by the openings through the 
dirt covering. If combustion takes place too slowly 
the openings are made larger; on the other hand, 
they are reduced in size if sufficient air is being ad- 
mitted to support a bright blaze. 

To make such charcoal into practical pigment it 
must be reduced to a fine powder by grinding. It must 
then be washed thoroughly, either in water or a dilute 
acid, to remove all impurities. 

A charcoal black, known as "vine black," is made 
from the lees and the pressed grapes used in the process 
of wine-making. In some of the wine-producing 
regions of Europe the industry of making charcoal for 
this vine black is quite an extensive one, and the pig- 
ment so produced is of very fine quality. The first 
step in the process of making this black is that of drying 
the lees at a moderate temperature. When the moisture 
has been removed the dried lees are placed in iron tubes 
(old stove-pipes, frequently) coated with clay, and 

[269] 



SCIENCE IN THE INDUSTRIAL WORLD 

surrounded completely except for a small vent for the 
escape of the gases in the subsequent heating-process. 
A very fine black pigment is made in practically the 
same manner from the remains of the pressed grapes. 

A form of charcoal made by the dry distillation of 
bones is known as bone black, or, in its finer qualities, 
ivory black. To make this pigment the bones are re- 
duced to small particles which are placed in closed 
crucibles and heated. As a result of this heating the 
inorganic portion of the bones is reduced to bone ash, 
while the organic portion is reduced to pure carbon and 
deposited on the inorganic particles. Thus the calcined 
substance contains only about twelve per cent, of carbon ; 
but this is sufficient for making a very good black pig- 
ment when the mass is ground to a fine powder. If a 
very pure article, such as that used by painters and 
black-and-white artists, is wanted, the bone ash may 
be removed simply by treating the ordinary bone black 
with hydrochloric acid, which dissolves the bone ash, 
thus liberating the particles of a very pure and very 
finely powdered carbon. 

It is rather curious that the soot from hard wood does 
not make good pigment, just as the charcoal from such 
wood does not. With this restriction, however, it may 
be said that good pigment may be made from any 
easily combustible substance that is rich in carbon, 
such as pine wood, resin, and the various animal and 
mineral oils. 

From the fact that all black printing-inks, and most 
of the best black paints and lacquers, are made from 
soot black, it may be correctly inferred that the manu- 

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PAINTS, DYES, AND VARNISHES 

facture of this product constitutes an enormous industry. 
The apparatus for its manufacture consists essentially 
of a chamber in which the substance rich in carbon 
can be burned at the lowest possible temperature, and 
some arrangement for catching the carbon and separa- 
ting it from the products of combustion. The primi- 
tive apparatus used in the pine regions, where the roots 
of pine trees are utilized for making soot black, is the 
same in principle as the more perfected apparatus de- 
veloped from it. It consists of a low flue built of ma- 
sonry, connected with which is a long wooden pipe. 
This pipe is lined with coarse cloth in order to give a 
rough surface upon which the soot is deposited. A 
brisk fire of dry wood is first started and kept up until 
the flue is thoroughly heated so that there will be little 
tendency for the soot to be deposited there and later 
consumed by accidental overheating. When the flue 
is thoroughly heated, pine roots and resinous chips are 
introduced and burned slowly, a dense, black smoke 
issuing from the tube as an indication of the state of 
combustion. 

Keeping such an apparatus at the right working 
temperature requires much skill, experience, and vigil- 
ance, as the workman has nothing but his natural senses 
to guide him. If the fire is too active there is likely to be 
combustion in the tube, and a loss of soot black, where- 
as if it is allowed to get too low a very poor product 
is obtained. The condition of the flame is regulated 
by the admission or exclusion of air in the flue, the ap- 
pearance of the flames indicating whether the amount 
of air is right or not. The ideal condition is difficult 

[271] 



SCIENCE IN THE INDUSTRIAL WORLD 

to describe. Generally speaking, however, the flame 
that produces the best soot is a long, dull, red one, with 
dark smoke issuing from the tip — much such a flame, 
indeed, as one sees in a smoky lamp. To keep this 
condition as nearly as possible, the workman opens and 
closes the " draughts" of the flue, these draughts con- 
sisting frequently of bricks which he piles before the 
opening or removes as the case requires. 

It is hardly necessary to say that in such a primitive 
soot-gathering apparatus the maximum quantity of 
high-quality soot is seldom obtained. In its perfected 
successor, however, very little of the soot escapes. 
Yet the difference between the two is one of construc- 
tion, not of principle. The better apparatus has the 
masonry flue supplied with necessary draughts with 
which the amount of air admitted can be regulated to a 
nicety. In place of the long wooden tube, a brick or 
cement tube is used, and this in turn connected with a 
high stack which is supplied with a damper. The 
pine root has been largely supplanted by resin for use 
in such furnaces, and a product of better quality and 
greater uniformity is obtained. However, even the 
very best product obtainable from pine or resin is not 
considered fine enough for the finer printing-inks, 
such as those used for making half-tone illustrations. 
These inks were made formerly from fatty oils or fish oils, 
this variety of soot black being known as " lampblack" ; 
but in recent years mineral oils and tar oils have been 
found to be satisfactory substitutes. When vegetable 
oils or fish oils are used, however, the cheaper and more 
rancid they are, the larger is the yield of lampblack. 

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PAINTS, DYES, AND VARNISHES 

For using any of these oils special lamps are made, 
having different kinds of burners adapted to the various 
oils, some of them being very much like the ordinary 
kerosene lamp used for illumination. As a rule, how- 
ever, a wickless burner of some kind is less expensive 
and preferable, such lamps being arranged so that they 
receive a continuous feed of oil, with an apparatus for 
regulating the supply of air, and a chamber for collect- 
ing the soot as it forms. 

The soot so formed is not pure carbon, but contains 
varying quantities of the products of distillation. For 
ordinary purposes, however, these impurities are not 
sufficient in quantity to impair the quality of the pig- 
ment. But if a perfectly pure carbon is required, it 
may be obtained by boiling the lampblack with a solu- 
tion of caustic soda, and then treating the residue with 
some acid. 

A very simple apparatus for obtaining a continu- 
ous supply of fairly good soot is one in which the flame 
of the oil lamp is brought in contact with a revolving 
iron cylinder, fitted with a water-chamber for keeping 
it cool. As the flames come in contact with this cooled 
surface the soot is deposited in a continuous line, which 
is removed by brushes placed on the opposite side of 
the cylinder, or at some convenient point. The soot so 
gathered is received on an inclined plane, down which it 
slides into the receiving-box. Such an apparatus is 
simple and inexpensive, and by its continuous action 
produces an enormous quantity of soot in the course of 
the working-hours of a day. 

The peculiar black pigment known as India ink is a 

vol. vm. — 18 [" 273 1 



SCIENCE IN THE INDUSTRIAL WORLD 

mixture of soot, glue, camphor, and musk. The best 
varieties of this pigment are made in China, and the 
exact process of its manufacture is still a secret. It is 
quite possible that the quality of the product is due 
to the method of manipulating the ingredients rather 
than to the quality of the ingredients themselves. By 
some it is thought that the superiority lies in the material 
from which the soot is made, or that it is made from a 
substance not readily obtainable in the West. It has 
been suggested, for example, that the soot may be made 
from the wood of the camphor tree, and that this is 
peculiarly adapted for making this particular pigment; 
but it seems more reasonable to suppose that it is the 
method of making, rather than the material contained, 
that makes the Chinese ink superior to the European. 

WHITE PIGMENTS 

White lead is one of the oldest known pigments. The 
Romans manufactured it and used it in great quanti- 
ties, and the name they gave it, cerussa, is still used in 
commerce. It is known also as flake white, Dutch 
white, Venetian white, Krems white, and by a score of 
other names. 

Chemically, white lead is a basic lead carbonate — 
that is, a compound of lead carbonate and lead hy- 
droxide; and commercially it is supposed to be this 
substance. In point of fact, however, it is found in the 
market adulterated with all manner of different sub- 
stances. Indeed, there are probably few commercial 
products that lend themselves so temptingly to adul- 

[274] 



PAINTS, DYES, AND VARNISHES 

teration, and in which the manufacturer so frequently 
yields to the temptation. Not long ago the United 
States government investigated the product of a sup- 
posedly reputable firm which had been widely adver- 
tised as a "pure lead-and-oil paint." The investigation 
proved that there was not one grain of lead or one drop 
of linseed oil in the much-heralded paint. From this it 
will be correctly inferred that white lead is a relatively 
expensive substance to produce. This production is 
accomplished by many different processes, although all 
of them are governed by the same general principle of 
chemical action. 

Briefly stated, this is the action of acetic acid upon 
metallic lead, producing a lead acetate, which is in turn 
acted upon by carbonic acid and changed to a lead 
carbonate. 

The three most commonly practised methods of man- 
ufacture are known as the Dutch (or German, or 
Austrian) process ; the French process ; and the English 
process. In the Dutch process, metallic lead is used as a 
basis ; in the French, lead acetate ; while in the English, 
litharge (lead oxide) is used. When metallic lead is 
used the metal is cast into sheets or strips, as metal 
so treated is much more readily acted upon by the acid 
than if pressed or drawn. 

The Dutch process is very old and very crude, but is 
still used extensively in some countries, and has the merit 
of making a good quality of white lead. In this process 
the vessels containing metallic lead and acetic acid are 
surrounded by manure, or by spent tan-bark, in a 
closed chamber. The heat generated by the fermenta- 

[275] 



SCIENCE IN THE INDUSTRIAL WORLD 

tion of this material facilitates the action of the acetic 
acid upon the lead in forming the lead acetate. At the 
same time carbonic acid, which is given off in the 
process of fermentation, combines with the lead acetate 
to form white lead. It takes from four to six weeks 
for the process to be completed, but at the end of that 
time from eighty to ninety per cent, of the metallic lead 
will have been converted into white lead, which is washed 
and ground into the white powder of commerce. 

Aside from the cost of the material in the manu- 
facture of white lead for pigment there is constantly the 
danger of poisoning during the process. White lead is 
an insidious poison, and the colics and paralyses of 
lead- workers have been known for ages. It is advisable, 
therefore, for manufacturers to provide mechanical 
means of conducting the operations of manufacturing 
their product; and this is required by law in many 
countries. 

The German or Austrian process of making the white 
lead is the same in principle as that of the Dutch, but 
in this method the heat and carbonic acid are produced 
by ordinary combustion. Specially constructed fur- 
naces are made in which the products of combustion are 
made to pass over the solution of lead acetate; and as 
carbonic acid is one of these products, a combination 
of this substance with the lead forms the lead carbonate 
or white lead. 

In the French process, the solution of the basic lead 
acetate is made from the metallic lead ribbons. Into 
this solution carbonic acid gas is passed, this gas being 
generated either by heating limestone, which produces a 

[276] 



PAINTS, DYES, AND VARNISHES 

very pure gas, or by the combustion of coal. This proc- 
ess was invented by the chemist Thenard, and is used 
extensively in France. 

For the English method, which is gradually dropping 
out of use, a stiff paste of litharge (PbO) is made by 
mixing it with a solution of lead acetate. This mass is 
kneaded by means of grooved rollers, through which 
carbonic acid is brought in contact with the paste. 
By this method a good quality of white lead was pro- 
duced only when the litharge was perfectly pure lead 
oxide. But as commercial lead oxide is often con- 
taminated with other oxides, such as copper and iron, 
white lead manufactured by this process is likely to be 
a mediocre product. 

Despite the fact that white lead has held first place 
among the mineral pigments for so many centuries, 
not only as a pure white pigment but as the basic sub- 
stance for forming other shades and colors, it is not, 
strictly speaking, a permanent white when used as a 
pigment. It is affected by sulphuretted hydrogen and 
the sulphides, and forms a black substance, lead sul- 
phide, when brought into contact with them. As the 
atmosphere everywhere contains more or less sulphur, 
or sulphides, the air of some cities being strongly con- 
taminated, the fate of every coating of white-lead pig- 
ment is eventually to turn gray, or even dead-black in 
time. This change is effected very gradually, of course 
— so gradually, indeed, that under ordinary circum- 
stances the other causes for the wearing-out of the coat 
of paint will make it necessary to repaint a building 
before the white lead has turned to more than a very 

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SCIENCE IN THE INDUSTRIAL WORLD 

light gray. In such a smoky city as London this change 
will naturally be much more rapid than in the open 
country where the air is practically free from sulphides. 
In such places as the vicinity of sewers, where the per- 
centage of sulphides in the air is very high, white-lead 
pigment turns gray very rapidly. Nevertheless, this 
defect in white lead is so completely offset by its good 
qualities, that it remains the most popular of pigments. 

The one quality above all others that endears it to 
the practical house-painter is its remarkable " cover- 
ing power" — the property of covering a great space 
with an opaque layer. But besides this, the lead paints 
are very durable, and may be used in an endless variety 
of combinations. 

If the question of permanency of color were the only 
thing to be considered in selecting a white pigment, 
however, the zinc, bismuth, and barium compounds 
would have a better standing than white lead, as all of 
them are less affected by atmospheric changes. In fact, 
the only really permanent white familiar to the paint 
trade is the sulphate of barium, known popularly as 
"enamel white. " This pigment will retain its pure 
whiteness indefinitely, even a long exposure to London 
smoke and fog having no effect upon it. Furthermore it 
can be produced for something less than half the cost 
of white lead. But when the relative covering powers 
and mixing qualities of the two are considered, practised 
painters regard white lead as the better pigment. 

In proof of this we find the painter always seeking a 
pure white-lead paint, while the dishonest manufacturer 
is forever trying to foist upon him a white-lead paint 

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PAINTS, DYES, AND VARNISHES 

adulterated with the cheaper sulphate of barium. And 
yet, if we may believe the results of the investigations of 
certain competent but disinterested persons, this prej- 
udice against the barium pigment is, in part at least, a 
traditional one, not justified by facts. Such investigators 
claim to be able to prove by practical demonstration that 
enamel white is quite as good a pigment as white lead — 
even better, indeed — and that it is destined slowly but 
surely to replace the more costly and poisonous material. 
That it has not done so hitherto, they say, is because 
it is so difficult, even in this age of iconoclasm, to over- 
throw beliefs that have been accepted as facts for so 
many centuries. 

Barium sulphate not only resists the action of the 
atmosphere, but is not affected under ordinary circum- 
stances either by strong acids or alkalis. It is found in 
nature as the mineral barytes, or heavy spar, and is 
sometimes obtained in so pure a state that it may be 
ground to powder and used as a pigment without further 
treatment. When treated in this manner, however, it 
is not so good a pigment as the product of chemical 
combination, as the particles cannot be reduced to such 
a fine state of subdivision by the mechanical process of 
grinding as they are by chemical action. 

When the enamel white is to be made from witherite, 
as the native barium carbonate is called, this substance is 
first dissolved in hydrochloric acid, and a solution of 
barium formed. Sulphuric acid is then added to the 
solution and in this manner the insoluble barium sul- 
phate, or enamel white, is formed, and thrown down as 
an insoluble precipitate. The particles of the barium 

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SCIENCE IN THE INDUSTRIAL WORLD 

sulphate thus formed are so tenuous that they will pass 
through the finest filter — a state of subdivision that can- 
not be approached by any known process of grinding. 
As the finer particles make the better pigment, it is 
obvious that the enamel whites prepared artificially are 
better than those prepared from the natural product. 

Another pigment that in many respects compares 
favorably with white lead, and which is only slightly less 
permanent than enamel white, is zinc oxide, known com- 
mercially as "zinc white.' ' In point of cost it has a 
disadvantage, costing somewhat more than white lead. 
On the other hand, ten parts of zinc-white paint are said 
to have as great covering power as thirteen parts of 
white lead, so that the initial cost is practically offset 
by the results. 

The zinc white of commerce comes on the market as 
a product from the zinc smelting-works, as it is formed 
when zinc vapor is burned in the air. It has the advan- 
tage over the lead pigments of mixing with pigments 
that contain sulphur without alteration. And since it 
is much lighter than the lead compounds, it is better 
adapted to mixing with the lighter vegetable pigments, 
such as the lakes. 

The white pigments just described may be taken as the 
most important ones for commercial purposes. There 
are a few others, such as those made from antimony 
compounds, and from bismuth, tin, manganese, and 
magnesia, which are of practical value for certain 
special purposes, but even in the aggregate these 
are relatively unimportant as compared with the lead 
and zinc compounds. 

[280] 



PAINTS, DYES, AND VARNISHES 



SOME " CHROME" PIGMENTS 

For making the yellow pigments — or more specif- 
ically, the chrome-yellow pigments — the compounds of 
the same three important metals, lead, barium, and zinc, 
are also the most important. Here again the product 
of the lead salts is the one most sought by the practical 
painter, although it is a very poisonous pigment, and, 
as the chemist points out, lacks the permanency of the 
other two. It has one cardinal point in its favor, con- 
ceded by both chemist and artisan : it is a more brilliant 
and beautiful yellow at first than any of the com- 
pounds of the other metals. But this brilliant color is not 
permanent, and when exposed for a long time changes 
to a dull color much inferior to the yellows of either zinc 
or barium. Nevertheless lead chrome yellow is the 
most popular of the yellow pigments to-day for general 
commercial purposes. 

Nature furnishes a lead chromate in the rare mineral, 
crocoisite, found in some lead mines; but the chrome 
yellow used for pigment-making is an artificial product. 
It is made by mixing a solution of potassium chromate, 
or bichromate, with a solution of some lead salt, fre- 
quently the acetate of lead. Curiously enough, the 
exact shade of color of the product depends to a very 
considerable degree upon the relative amounts and 
strengths of the two solutions used. In the ordinary 
chemical reaction the molecules of the resulting com- 
pounds will be the same, whatever the relative propor- 
tions of the basic solutions; but in the production of 

[281] 



SCIENCE IN THE INDUSTRIAL WORLD 

lead chrome yellow the exact shade can be determined 
by the amount of the two liquids used. By under- 
standing this it is possible for the manufacturer to pro- 
duce a lighter or darker shade at will. To produce the 
numerous shades of yellow that cannot be made directly 
by the initial process, varying quantities of white lead 
are used. These may be added after the process of pre- 
cipitating the chrome lead is completed, or may be pre- 
cipitated at the same time. The white-lead salts add 
greatly to the brilliancy of the pigment. 

In some instances there is a chemical combination 
between the lead chromate and such a salt as the sul- 
phate, so that the resulting light-yellow compound 
is not merely a mechanical mixture of two lead salts, 
but is a chemical compound. 

When the manufacturer wishes to produce one of 
these pale shades of yellow he adds a certain quantity 
of sulphuric acid to the solution of the chromate used, 
and mixes this with the acetate-of-lead solution. In the 
reaction that follows a certain quantity of the white 
sulphate of lead is formed with the lead chromate, and 
is precipitated with it, either as a chemical combination, 
as we have just said, or as a mechanical mixture having 
a perfectly uniform color. The shade of color so pro- 
duced will vary with the amount of sulphuric acid used, 
larger quantities of the acid making corresponding 
lighter shades of yellow. The process of making zinc 
chrome yellow, and barium chrome yellow, is very 
much the same as for making the lead chrome yellow. 

Nature furnishes another lead pigment in the form of 
lead monoxide (PbO) which, in its crystalline form, is 

[282] 



PAINTS, DYES, AND VARNISHES 

called litharge, and in its amorphous form, massicot. 
The crystalline salt is a dull yellow, while the amor- 
phous one is a reddish yellow. These substances are 
not used very generally as pigments, although there is 
another lead oxide, in which the molecule contains lead 
and oxygen in the proportion of three to four (Pb 3 4 ), 
which is the bright-red pigment used by plumbers as a 
cement for pipes. 

A yellow which is distinctly inferior in quality to the 
chromic-acid salts of lead, zinc, or barium, is calcium 
chrome yellow. It is a very permanent color, however, 
and is much cheaper than the other three, so that it is 
popular in places where price and permanency, rather 
than beauty, are the principal conditions. 

" Turner's yellow," which was invented by James 
Turner late in the eighteenth century, and was popular 
for many years, is a pigment that has been superseded in 
later years by the chrome and ochre pigments which will 
be presently described. It was an oxy chloride of lead, 
made from litharge and ammonium chloride, and was 
known under the various names, Montpelier yellow, 
Cassel yellow, Kassler yellow, Verona yellow, and 
probably others. 

" Naples yellow/' a compound of the oxides of an- 
timony and lead, which was a popular pigment at one 
time, has also been replaced by the chromes, over which 
it has no advantage. 

A beautiful and permanent chrome yellow is made 
from the metal cadmium, but this pigment is too ex- 
pensive for ordinary commercial purposes. It is some- 
times used as an artist's pigment, but more generally 

[283] 



SCIENCE IN THE INDUSTRIAL WORLD 

the cadmium yellow, which is made by the action of sul- 
phuric acid upon the metal, is preferred. 

Mars yellow, which is quite a favorite with artists, is 
a mixture of oxide of iron with calcium or aluminum 
sulphate, while aureolin is a double nitrate of potassium 
and cobalt. There are also yellows made from arsenic, 
mercury, antimony, and thallium that are sometimes 
used for pigments; but none of these has any great 
value commercially as compared with the chrome yel- 
lows enumerated. 

The familiar yellow seen in the gilding of picture- 
frames, which rivals gold in luster, is a bisulphide of tin 
(SnS 2 ). It is known as " mosaic gold," and is made by 
heating together tin filings, sulphur, and ammonium 
chloride, the relative proportions being varied con- 
siderably by different manufacturers. In the heating- 
process care must be taken not to raise the temperature 
too high. It is to prevent this that the ammonium 
chloride is used. This salt volatilizes at a relatively 
low temperature, and so long as this volatilization is 
going on, the general temperature of the mass contain- 
ing it will not be raised high enough to injure the 
product. By this process a pigment may be made, 
the luster of which closely rivals the pure metal it is 
made to imitate. 

A cheaper and inferior mosaic gold can be made by a 
wet process, in which the bisulphide of tin is precipitated 
from the solution of a tin salt by the action of sulphur- 
etted hydrogen. When prepared in this way, however, 
the pigment not only lacks luster, but is of a distinctly 
inferior color. 

[284] 



PAINTS, DYES, AND VARNISHES 



OTHER YELLOW MINERAL PIGMENTS 

The principal yellow mineral pigments are the 
chromes and ochres, although there is a long list of 
yellows and oranges from other sources that are oc- 
casionally used. The base of all the chrome pigments 
is the chromate of lead (PbCrO) and its basic modifica- 
tions. The lead chromates are readily obtained by 
mixing a solution of potassium bichromate with a solu- 
tion of lead acetate, and vary in color from light yellow 
to deep red. As placed on the market commercially, 
the darker shades are likely to be pure lead chromates; 
while the lighter shades represent a mixture of the darker 
base with some white pigment, such as sulphate of lead, 
or enamel white. These mixtures do not necessarily im- 
pair the quality of the pigment. Indeed the "pure 
chromes" of commerce are really mixtures with the 
lead sulphate. Thus "pure" lemon yellow is made 
from the following formula : 

Lead acetate (or nitrate) ioo parts 

Bichromate of potash 25 " 

Sodium sulphate 35 " 

If this formula is varied a little, such as by increasing 
the amount of bichromate of potash five parts, and the 
sodium sulphate diminished fourteen parts, "pure" 
chrome yellow is formed. And if the sodium sulphate 
is omitted entirely, "deep" chrome yellow is made. 
Still other shades may be produced by using sulphuric 
or nitric acid in place of the sodium salt; and these 
may be varied again by using a barium salt with the 
lead acetate and potassium bichromate. 

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SCIENCE IN THE INDUSTRIAL WORLD 

By using white lead, potassium bichromate, and 
caustic soda in certain proportions and boiling for a 
short time, a red of considerable brilliance is formed, 
which is known commercially under various names, 
such as Persian red, Victoria red, American vermilion, 
Chinese red, Derby red, chrome red, and several less 
familiar names. 

The chrome-lead pigments are, almost without ex- 
ception, very good pigments from the practical painter's 
standpoint. They have good covering powers, bril- 
liancy, and permanency under ordinary conditions. 
They have the defects of all the other lead pigments, 
but their good qualities are so pronounced that, for 
yellow paints, they may be said to have scarcely any 
competing rivals for first place commercially. 

The zinc chromes, while distinctly inferior to the 
lead chromes as pigments, are, nevertheless, important. 
The method of making them does not differ essentially 
from that of making the lead chromes, except that a 
zinc salt is used in place of a salt of lead. This salt is 
mixed in definite proportions, either with chromic acid, 
or with bichromate of soda, or potassium. The tints 
obtained from these mixtures are known severally 
in commerce as "marigold tint," "lemon tint," "pale 
tint," "zinc chrome," "deep chrome," etc. Most of 
these pigments have good color and body, and mix 
readily with other pigments. 

Ranking next in importance to the chromes as yellow 
pigments, although usually considered distinctly in- 
ferior to them, are the natural mineral pigments, ochres 
and siennas. These substances are widely and abun- 

[286] 






PAINTS, DYES, AND VARNISHES 

dantly distributed throughout the mineral world, al- 
though the quality of the product varies greatly in 
different regions. The color of the ochres is due to the 
presence of hydrated peroxide of iron; and while this 
substance gives the color to the siennas also, it is modi- 
fied in these pigments by the presence of small quantities 
of manganese. With these substances there is always 
a mixture of various " earths," so that the pigment is a 
conglomerate mixture of several chemicals. Some of 
these mixtures occur in such natural deposits that they 
may be used as pigments of good quality without 
treatment other than that of grinding to a fine powder. 

When ochres are heated they turn red, and are 
sometimes marketed as Venetian red, or Indian red. 
When the siennas are heated, however, a reddish- 
orange shade, known as burnt sienna, is produced. 
The cause of this change of color is probably the con- 
version of hydrated iron oxide to an anhydrous 
state; but as yet we do not know just why the ochres 
turn red, while the siennas have orange color during 
the process. 

That the composition of ochres is complicated is 
shown by the following analysis of Oxford ochre, by 
Hurst:— 

Water, hygroscopic 6. 887 per cent. 

Water, combined 8. 150 " 

Calcium oxide o. 998 " 

Sulphur trioxide 1 . 32 1 " 

Alumina 6 . 475 " 

Ferric oxide 12.812 " 

Silica 63 . 478 " 



[287] 



100. 121 



SCIENCE IN THE INDUSTRIAL WORLD 

The siennas differ very little from the ochres in 
composition except for the addition of manganese. The 
quantity of this is so small, however, that it is only recog- 
nized as a "trace" by the chemists in the analysis, yet 
this "trace" is sufficient to alter the color. 

An important pigment that is a favorite with some 
artists on account of its brilliancy, is cadmium yellow, 
which has the chemical formula CdS. It is permanent 
and is obtained in several shades of yellow and orange 
and mixes well with most other pigments. 

Among the yellow mineral pigments that have largely 
been replaced by some of the foregoing, are the "Mars 
colors" which were sold in many shades under various 
names. These colors possess no advantage over the 
ochres, and have the disadvantage of costing more. 
Mention has been made above of how the lead pigments, 
"Turner's yellow" and "Naples yellow," have also 
yielded to the chromes. The same is true of "King's 
yellow," which is a bisulphite of mercury. 

Aureolin, a pigment lacking permanency, is still in 
use. It is a double nitrate of potassium and cobalt, 
and was at one time very popular with artists. 

SOME BRILLIANT BUT POISONOUS PIGMENTS 

We have seen that the pigments made from lead are 
poisonous compounds which must be handled with 
caution, both in the process of manufacture and in the 
subsequent operations of painting. Far more poison- 
ous than the lead pigments, however, are those made 
from the metal mercury, which is the essential constitu- 

[288] 



PAINTS, DYES, AND VARNISHES 

ent of the most brilliant of the mineral red pigments, 
vermilion. Indeed, it is an unfortunate fact that most 
of the permanent mineral pigments — the green of ar- 
senic, the blue of the prussic-acid compounds, as well 
as the compounds of lead and mercury, are poisonous. 

Chemically, vermilion is a mercuric sulphide, having 
the formula HgS. It is found in nature as cinnabar, 
and the selected pieces of this mineral are placed on the 
market as " mountain vermilion." This is usually an 
inferior pigment, however, most of the vermilion on the 
market being an artificial product. 

There are two forms of the mercuric sulphide, a 
non-crystalline one, black in color, and the one of crys- 
talline form, known as vermilion. Either one of these 
may be produced from the other by proper manipula- 
tion; and in practice the red sulphide is frequently 
made from the black. 

Black sulphide may be made by the simple processes 
of stirring together equal parts of mercury and sulphur 
moistened with water, a mixture of mercury and 
ammonium sulphide, or by heating mercury and sul- 
phur together. It is a velvety, black mass, which is 
changed into the crystalline sulphide, or vermilion, by 
heating to a temperature at which it volatilizes. 

Chinese vermilion, which is superior in quality and 
shade to Western vermilions, is a mercury product pre- 
pared by some process unknown to Europeans. The 
alleged method of making it has been told many times, 
but the true method probably still remains a secret of 
the Orientals. It is a very expensive pigment; but so 
also are the Western vermilions, even the cheapest of 

vol. vm.— 19 [ 289 ] 



SCIENCE IN THE INDUSTRIAL WORLD 

which cost so much that there is constant temptation 
for dishonest manufacturers to adulterate them. Most 
of these adulterants are combinations of lead and iron 
pigments, some of which give a color closely simulating 
true mercury vermilion, but all of them lack the per- 
manency and fineness of shade of the more expensive 
pigments. 

A close rival of the mercury vermilion, in the matters 
of shade and permanency, is antimony vermilion, which 
is a trisulphide of antimony. Commercially, however, 
it cannot be considered a great rival, although it seems 
to have many qualities that would entitle it to such a 
place were it not for the established prejudice in favor 
of the older pigment. It is much less expensive than 
true vermilion, and this advantage seems to be gradually 
bringing it into favor with practical painters. 

For several reasons the ferric-oxide reds, which are 
sold in the market under such names as Venetian red, 
Indian red, scarlet red, purple oxide, rouge, and several 
other less general names, are favorite pigments with 
painters. They are relatively cheap, permanent under 
all conditions, and when mixed with other pigments 
for the most part do not affect them and are not affected 
by them. They are found in a natural state, sometimes 
so pure and of such quality that the mineral may be 
powdered and used as a pigment without further treat- 
ment. This is not usually the case, however, and most 
of these pigments are manufactured artificially by one 
of the many processes known to chemist and paint- 
manufacturer. 

Another red pigment that is a great favorite for many 
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PAINTS, DYES, AND VARNISHES 

kinds of protective and decorative purposes, is red lead 
— a lead oxide having lead and oxygen in the molecule in 
proportion of three to four, Pb 3 4 . It is probable that 
these proportions are not quite as exact as in the in- 
dicated chemical formula, for, as we have seen, chemical 
formulas and colors do not always correspond ; but this 
formula represents the composition very closely. 

Red lead has good coloring and covering powers, and, 
under ordinary atmospheric conditions, is permanent. 
It has the defect of all the lead pigments of being 
affected by sulphuretted hydrogen, but under ordinary 
conditions this is so slight that it need not be considered. 
It has a powerful drying effect upon linseed oil, and this 
quality adds to its value for many purposes, such as 
packing the joints of steam-pipes. 

Another form of red lead — a pigment having the same 
chemical composition as far as can be determined, 
although of different color — is orange lead. It is paler 
in color, and lighter in weight, and is made by a dif- 
ferent process, but what may be the difference in the 
arrangement of the atoms in the molecules that makes 
a different shade still remains a mystery. 

Among the other red mineral pigments which are of 
little practical importance, although, in some instances, 
of brilliant color, are the chromium salts of lead, mer- 
cury, copper, and silver. Most of them are lacking in 
permanency and are too costly for general use, al- 
though chrome lead is an exception, and will be re- 
ferred to again in a moment. 

The biniodide of mercury is also a brilliant color — 
"brilliant scarlet," it is called in the trade. It is very 

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SCIENCE IN THE INDUSTRIAL WORLD 

fugitive, however, and is only useful where a tempo- 
rarily brilliant effect is desired. A very pale, although 
permanent, red is prepared from magnesia and nitrate 
of cobalt, but this pigment is not in general use. 

GREEN MINERAL PIGMENTS 

Of the green mineral pigments probably the most im- 
portant for ordinary painting are the various shades of 
Brunswick green. Emerald green, the poisonous 
substance known as "Paris green" in America, which 
was once very popular as a pigment, and is still used 
by artists for their purposes, has now been replaced 
largely by a coal-tar product which will be referred to a 
little later. The true chrome green and other copper 
greens are also of considerable importance as pigments, 
and there are several others. 

The so-called Brunswick greens formerly in use were 
compounds of copper; but these have now been com- 
pletely supplanted by the more modern greens of the 
same name but of different compositions. The modern 
Brunswick greens, which are known commercially as 
"pale," "middle," "deep," "extra-deep," etc., are 
mixtures of barytes, Prussian blue, and chrome yellow, 
or compounds of similar chemicals in varying propor- 
tions. The relative amount of Prussian blue determines 
the shade of the green pigment, the larger the amount 
the deeper the shade. Thus one hundred parts of 
barytes, two parts of Prussian blue, and thirty-five 
parts of chrome yellow make a pale Brunswick green; 
whereas if the amount of Prussian blue is increased to 

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PAINTS, DYES, AND VARNISHES 

eight parts, a very deep shade of Brunswick green is 
produced. Of course the quality and color of the Prus- 
sian blue and the chrome yellow have to be taken into 
consideration, but the general rule holds good in any 
case. 

As pigments, the Brunswick greens work well either 
in oil or water. They have good covering power, and 
as they are permanent enough for all practical purposes, 
and mix well with most other pigments, they are favorites 
with practical painters. 

The chrome greens, which are usually mixtures of 
oxides and phosphates of chromium, are very popular 
pigments with both artists and artisans, on account of 
their brilliance of color, permanence, and good mixing 
qualities. When mixed with other oil pigments they 
remain unchanged, and have no effect upon the other 
pigments; but as water-colors they change slightly 
in time. In the experiments conducted by Messrs G. 
Rowney & Company, of London, to determine the per- 
manency of various colors, the specimen of chrome green 
mixed with flake white and exposed to sunlight for twelve 
months showed only the slightest change from the 
original shade. 

There are several copper greens which at various 
times in the past have been important as pigments, but 
all of these have gradually ceased to be of importance 
to the painter. Of these verdigris, Scheele's green, and 
emerald (or Paris) green, form a group similar in com- 
position, each one of which has had its period of popu- 
larity only to be supplanted by another pigment. Verdi- 
gris, an acetate of copper, is the oldest and poorest 

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SCIENCE IN THE INDUSTRIAL WORLD 

pigment of this group. It was supplanted as a pigment 
soon after 1778, when the Swedish chemist, Scheele, 
announced the discovery of the pigment that has since 
borne his name. This is a basic arsenite of copper, and 
although somewhat better as a pigment than the copper 
greens known before its discovery, it cannot be con- 
sidered as a high-class pigment, and dropped out of use 
after the discovery of emerald green in 18 14. This green 
is an aceto-arsenite of copper, and is very poisonous. It 
has good covering power, brilliant color, and in dry 
places is very permanent ; but on account of the dangers 
attending its use it has fallen into disfavor as a pigment 
except with artists. This waning in popularity of emer- 
ald-green as a pigment for over half a century, has been 
offset by a corresponding increase in popularity of this 
substance as an insecticide. Thousands of bushels of 
vegetables are saved annually by the use of Paris green. 

Of the other copper-green pigments, a basic carbonate 
known as " mineral green," or " malachite," occurs as a 
natural green mineral in several places on the earth. 
Green verditer is also a basic carbonate of copper which 
is made artificially, as is also Bremen green. But 
none of these substances need be considered seriously 
in the list of practical pigments in use to-day. 

Terre verte, or Verona green, as it is sometimes called, 
is a natural green mineral pigment of very complex com- 
position. It contains silica, ferrous oxide, potash, mag- 
nesia, and possibly alumina, soda, and manganese. 
It is very permanent as a pigment, and was used ex- 
tensively by the ancient and medieval painters, who had 
no other permanent green pigment. It is poor in body 

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PAINTS, DYES, AND VARNISHES 

and coloring, and has lost its former popularity since 
the discovery of so many other brilliant greens. 

One of these brilliant greens is the compound of the 
oxides of zinc and cobalt, known as cobalt green. For 
commercial painting this pigment is too expensive, but as 
an artists' color it is very popular. It is permanent, not 
affected by mixing with other pigments, and has good 
covering power. On account of these qualities, numer- 
ous efforts have been made to find a cheap way of 
manufacturing it commercially, but so far these have 
been unsuccessful. 

Besides these mineral greens there are others, such as 
zinc green, titanium green, manganese green, and 
Brighton green, that have been employed more or less 
extensively at different times, but are of relatively 
little importance at present. Zinc greens are made by 
mixing zinc chrome, Prussian blue, and barytes. Ti- 
tanium green is a ferrocyanide of titanium which was 
made originally as a substitute for the arsenical greens, 
but is too expensive for practical purposes. Manganese 
green is essentially a manganate of barium, and is used 
very little as a pigment. Brighton green is a preparation 
of the basic acetate of lead. 



BLUE PIGMENTS FROM THE MINERAL WORLD 

Although the various shades and tints of blue are 
among the most important as colors, the number of blue 
mineral pigments is relatively small. Fortunately 
this deficiency in number is more than counterbalanced 
by the permanency of these pigments. The three most 

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SCIENCE IN THE INDUSTRIAL WORLD 

important are ultramarine, Prussian blue, and cobalt 
blue. 

The pigment ultramarine, as used by the ancients, 
was literally "worth more than its weight in gold," 
as was said a few pages back. For this pigment was 
made by grinding to powder the semi-precious stone, 
lapis lazuli, found only in China, Siberia, and Persia. 
Its cost, therefore, placed it outside the realm of com- 
mercial pigments; and only the opulent among the 
artists could afford to use it. It was made by grinding 
the mineral to a fine powder, mixing this with a com- 
pound of resin, wax, and linseed oil, and kneading the 
mixture in a bag immersed in hot water. The blue 
color comes through the cloth into the water and finally 
settles. It is a tedious process of ancient origin, and yet 
no simpler or better method has ever been discovered 
for making the ultramarine pigment from the mineral. 

Even if such a method had been discovered, the pig- 
ment would still have been far too expensive for general 
use, owing to the cost of lapis lazuli itself. But early 
in the nineteenth century, when the infant science of 
chemistry was doing so much to solve the hitherto elu- 
sive riddles of Nature, practical chemists effected the 
analysis of the mineral ultramarine with a view to its 
artificial production. The day of great triumphs of 
analytical and synthetic chemistry had just dawned, 
and one of the first was the production of an artificial 
ultramarine product superior in quality to the natural, 
and costing less than a thousandth part as much. 

Analysis had shown ultramarine to be largely a com- 
pound of the common substances, silica, aluminum, 

[ 29 6] 



PAINTS, DYES, AND VARNISHES 

lime, soda, sulphur — plebeian substances in them- 
selves, that become of such regal importance when 
combined in the proportions to form the material 
ultramarine. And now the "Societe d' Encouragement 
de France" offered a prize of six thousand francs to 
"anyone who would effect this combination syntheti- 
cally, and produce ultramarine in wholesale quantities." 
This prize was soon won (in 1828) by the eminent 
French chemist, Guimet, who was able to make the 
pigment on a large scale at a very low price. The exact 
method used by Guimet was kept secret, and still re- 
mains so; but as his discovery was followed shortly 
by the discovery, by several other chemists, of processes 
leading to similar results, his precise method of proce- 
dure is of historical importance only. 

At the present time there are two general methods of 
manufacture, each of which is subject to certain varia- 
tions. In one of these a mixture of kaolin, soda, 
charcoal, quartz, resin, etc., is first calcined, forming 
a green substance known as ultramarine green. To 
convert this into blue ultramarine a second heating- 
process with sulphur is necessary. In the other method 
the process is completed in one heating, and as this 
also gives the better pigment, it is the one most generally 
used. Hurst describes one of these methods as follows: 

"A very good mixture to use is — 

Kaolin 76 parts 

Sodium carbonate 60 " 

Sodium sulphate 15 " 

Sulphur 78 " 

Charcoal 16 " 

Diatomaceous earth 18 " 

Quartz 10 " 

Resin 12 " 

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SCIENCE IN THE INDUSTRIAL WORLD 

"All these ingredients are ground together into a 
homogeneous mass; this is a point of great importance. 
The mixture is loosely packed into crucibles fitted 
with flat lids, which are luted on by means of mortar. 
When the mortar-luting is dry the crucibles are piled in 
ovens large enough to hold 400 to 500 crucibles. . . . 
After all the doors and openings into the oven are made 
up, it is fired to a bright-red heat for several hours, the 
length of time varying considerably and depending upon 
a number of factors such as the state of the weather, the 
composition of the mixture, etc. Experience is the only 
school in which the ultramarine-maker can learn how to 
regulate the time required. 

" After the heating, all the apertures are carefully 
closed, so as to exclude air, and the furnace allowed to 
cool for four or five days; the oven is then opened, 
and the crucibles withdrawn and opened, the con- 
tents turned out, and the badly burnt pieces care- 
fully separated; the good portions are ready to be 
finished. 

"The changes which go on during the heating of the 
mixture are both curious and interesting. The mixture 
when first put into the crucibles is of a grayish color, 
but during the process of burning it passes through a 
series of color-changes — brown, green, blue, violet, red, 
and white. The brown appears with the blue flames, 
due to the burning of the sulphur; it is a fine chocolate- 
brown but is very unstable; on exposure to the air it 
enters into combustion. Many efforts have been made 
to preserve it, but these have been fruitless. The 
green, which is the next change, begins to form when 

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FAINTS, DYES, AND VARNISHES 

the sulphur has ceased to burn; like the brown it is 
unstable, as the substance burns on exposure to the air. 
Following the green comes the blue, which is formed 
when the temperature has reached about 700 C, or a 
bright-red heat; when the temperature gets higher the 
color changes to a violet. With still higher tempera- 
tures, first a red, then a white variety is formed. These 
changes are due to oxidation; when the white ultra- 
marine is heated with reducing agents, such as carbon, 
the colors are re-formed in the reverse order to that in 
which they first appeared." 

The ultramarine as it comes from the furnace must 
be " finished" by grinding, and there are other manip- 
ulations subordinate to the process described. The 
essential thing is that it is possible now to make this 
most useful pigment for such a small amount that 
it is one of the cheapest of painters' colors. 

A blue pigment that is a close rival of ultramarine is 
Prussian blue (known also as Berlin blue, or Chinese 
blue) which is a ferric ferrocyanide — a complex com- 
pound of iron, carbon, and nitrogen, the last two ele- 
ments combined in the form of the radical known as 
cyanogen. It was discovered accidentally by the 
Prussian color-maker, Diesbach, early in the nineteenth 
century. Diesbach was engaged in the manufacture of 
a red lake pigment, when, happening to use an alka- 
line solution which had been employed in some treat- 
ment of ox blood, he found that quite by chance he had 
produced a beautiful blue pigment. Following up this 
accidental discovery, he soon was able to produce the 
pigment, Prussian blue, and place it upon the market 

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SCIENCE IN THE INDUSTRIAL WORLD 

in any desired quantities. Other color-makers took up 
the problem at once and soon solved it by various meth- 
ods, so that this color took its place beside ultramarine 
as a regular commercial product. 

Very fine grades of Prussian blue are frequently 
designated as "Chinese blue," and may be made in the 
following manner: — 

One hundred parts of sulphate of iron are dissolved 
in cold water and ten parts of sulphuric acid added to 
the solution. This solution is then mixed with a 
solution of one hundred parts of yellow prussiate of 
potash. As a result, a bluish- white precipitate is formed, 
which settles to the bottom of the vat. To this precipi- 
tate a mixture of about twenty parts of bleaching- 
powder and water is added, and thoroughly stirred, 
after which a little hydrochloric acid is poured in, on 
the addition of which the characteristic blue color 
gradually develops. This blue pigment settles to the 
bottom in a thick mass from which the overlying liquid 
is run off. It is then washed, drained, and finally 
pressed into pans and dried in dark ovens at a tempera- 
ture not higher than 130 F. This is, of course, only 
one of the many methods of manufacture, but it may be 
taken as a characteristic one. 

The Prussian blues have a characteristic greenish- 
blue tint not seen in any other pigment. They are 
permanent as oil-colors, and their coloring power is 
remarkable, one part of Prussian blue giving a dis- 
tinctly blue color to six hundred parts of white lead. 
When used as a water-color Prussian blue has the pe- 
culiarity of fading considerably when exposed to light 

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PAINTS, DYES, AND VARNISHES 

for any length of time, but of recovering its original 
shade when placed in the dark. 

Cobalt blue, the third important blue mineral pig- 
ment, is known commercially in two forms, "smalt," 
and cobalt blue. Smalt is really a glass colored by 
cobalt, and is a very old pigment. In recent years its 
popularity as a pigment has declined as it is inferior to 
artificial ultramarine. 

True cobalt blue is a favorite color with artists, 
particularly with those who work in water-colors, on 
account of its permanency and mixing qualities. It is a 
compound of the oxides of aluminum and cobalt, with an 
occasional trace of phosphoric acid. It may be made in 
various ways, perhaps the best method being that of dis- 
solving nitrate of cobalt in water, and to this solution 
adding sufficient sodium phosphate to precipitate the 
cobalt as phosphate of cobalt. After this precipitate is 
washed with water it is mixed with a precipitate of 
alum and sodium carbonate in the proportion of one part 
cobalt to eight parts aluminum. This is then heated 
to a red heat and kept at that temperature until the blue 
color is fully developed, the process requiring from 
one-half to three-quarters of an hour. 

The three blue pigments just described — ultramarine, 
Prussian blue, and cobalt blue — have practically dis- 
placed all the older blue metallic pigments, such as those 
made from copper. Such pigments as mountain 
blue, Bremen blue, blue verditer, which are all com- 
pounds of copper; and lime blue, which is a mixture 
of copper hydroxide and calcium sulphate, are now of 
interest historically only. But of far greater interest in 

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SCIENCE IN THE INDUSTRIAL WORLD 

this respect is the pigment "caeruleum" — the blue 
pigment used by the Egyptians, which has resisted the 
action of time and the elements for several thousand 
years in many known instances. It is this blue pigment 
that may still be seen in the ruins of Pompeii, Cairo, 
and Alexandria; but it is only within the last quarter 
of a century that its chemical composition has been 
known. Fouque, the French chemist, found it to be — 

Silica (Si0 2 ) 63 . 7 per cent. 

Calcium oxide (CaO) 14. 3 " 

Copper oxide (CuO) 21.3 " 

Ferric oxide (Fe 2 O s ) 0.6 " 

It is therefore, probably, a double silicate of copper 
and calcium, and Fouque believes that the ancients made 
it by fusing together roasted copper ore with lime and 
sand. 



THE BROWN MINERAL PIGMENTS 

The brown mineral pigments, constituting a small 
but important group, are mostly natural pigments. 
The most important of these is umber, a substance 
closely resembling the ochres and siennas, but contain- 
ing more manganese, which is probably the cause of 
the darker color. The umbers vary in hue from violet 
brown to reddish brown, and are found in thick mineral 
deposits in strata sometimes thirty feet in depth. They 
are found in almost every country, but the finest comes 
from Cyprus. 

Commercially, umber is marketed in lumps, just as it 
comes from the mines, or in a powder, which is simply 

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PAINTS, DYES, AND VARNISHES 

the natural product, ground and levigated. Burnt 
umber, which has a darker and warmer color than 
the raw mineral, is made by heating the natural umber 
to a red heat. 

Chemically, umber is a very complex substance, 
specimens from different sources showing considerable 
variation in this respect. Among its components are 
silica, manganese, aluminum, calcium carbonate, ferric 
oxide, and barium sulphate. The color of umber is per- 
manent; it mixes well with other pigments, and for 
these reasons, and because of its cheapness, it is a favorite 
with painters and artists. 

Vandyke brown is a pigment made from several 
natural deposits, some of them of peaty origin, and 
named after the great Dutch painter on account of his 
fondness for brown colors. It is also manufactured 
from the cuttings of cork that have been calcined. The 
common Vandyke browns for sale in the market are 
usually mixtures of some black pigment, such as lamp- 
black, with red oxide of lead and yellow ochre. They 
are good pigments, however, mixing well with other 
colors, and being practically permanent under all 
conditions. 

PIGMENTS FROM VEGETABLE AND ANIMAL SOURCES 

Generally speaking, it may be said that the pigments 
from animal and vegetable sources are of greater im- 
portance than those of mineral origin to the dyer, while 
to the painter the reverse is the case, although there 
are certain pigments from every source of great 

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SCIENCE IN THE INDUSTRIAL WORLD 

importance to both. But even substances of purely 
organic nature, when used as pigments are usually 
combined with some metallic substance. Thus, the 
important class of pigments known as the "lakes" are 
compounds of an organic coloring-principle with a 
metallic body. 

The lakes seem to derive their name from the ancient 
Italian dyers, who called the colored scum which rose to 
the surface of their dye-vats, lacca. This they gathered 
and sold to artists as a pigment, which came to be known 
eventually as "lake" pigment. 

Until recent years the organic coloring-principle of the 
lake pigments was derived from cochineal insects, 
madder red, Persian berries, Brazil wood, sapan 
wood, fustic, and several other sources; and these 
sources continue to be of importance to-day. But the 
discovery of the products of coal-tar revealed, among 
other things, that all manner of lake colors could be 
made from that peculiar substance ; and as a result the 
animal and vegetable worlds have been largely shorn of 
their importance as the source of pigments. Indeed, it 
seems so certain that the pigments from animal and 
vegetable sources will eventually be replaced by those 
derived from coal-tar, and similar mineral products, 
that a description of the method in use to-day of making 
a vegetable pigment may have only historical impor- 
tance and interest to-morrow. 

Aside from white pigments, there is no shade or 
color that cannot be made from the lakes. Some of these 
are fugitive and of little use as permanent pigments, 
while others, such as carmine, make the "finest and most 

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PAINTS, DYES, AND VARNISHES 

expensive colors used in painting." Since there is such 
an array of these colors, many of which have been 
named and renamed many times, it is obviously im- 
possible to consider each in detail, and a description of a 
few of the most important will suffice for our purpose 
here. 

The original source of the finest of all pigments, car- 
mine, was the North American continent, although the 
cultivation of the cochineal insect, from which the color 
is derived, has now extended to all tropical countries. 
When the soldiers of Cortez first invaded the Aztec 
empire in Mexico, they found the natives using a bril- 
liant, red dye obtained from insects that were parasitic 
upon certain cactus plants. Only the female insect 
is used for coloring-material, the males being much 
smaller and fewer in number. The female insects 
cling to the cactus leaves in enormous numbers, from 
which they are brushed onto heated metal plates, and 
killed. 

These insects contain as high as fifty per cent, of 
the coloring-matter called carmine, which is the same 
name given to the lake made from it. It is obtained by 
reducing the dried insects to a pulp, and afterward 
macerating them in water. The coloring-matter is then 
precipitated with an aluminum salt, great care being 
taken to have all the materials used perfectly pure, as 
any impurities affect the shade. Thus the impurities 
contained in ordinary water, or even the minerals in 
spring water, may injure the color if such waters are 
used. It is customary, therefore, to use distilled water 
in the process of manufacture. And the same care 

vol. viii.— 20 r ^O^ 1 



SCIENCE IN THE INDUSTRIAL WORLD 

that is taken in selecting the water is applied to all 
the other substances used. For it has been demon- 
strated many times that herein lies the secret of making 
fine carmine pigment; whereas it was supposed for 
many years that some special and obscure process was 
necessary. 

Carmine, besides being the most brilliant and beauti- 
ful red color known, has the advantage over most of 
the other reds of being non-poisonous. It can be used 
for coloring foods, and is used extensively in tinting 
confectionery and various preserved fruits. 

Practically the only drawback to the use of carmine 
in almost every field where bright colors of the paler 
tints of red are used, is its cost. It has never been 
possible, even in the vast territories of the tropics where 
the little cochineal insects flourish, to produce them in 
sufficient quantity to supply the demand for their color- 
ing-matter. Consequently the price of carmine has 
always been very high. But all this is now changing. 
The pale workers of the laboratory have found a means 
of doing what the bronzed men of the fields could never 
accomplish. They have found a way of supplying un- 
limited quantities of an artificial carmine, made from 
coal-tar, at a mere fraction of the cost of the older 
product — a synthetic carmine, quite as good as the nat- 
ural pigment. So after centuries of useful bondage in 
the service of savage and civilized man, the little Mexican 
insect seems to be serving the last years of its usefulness, 
and will very shortly be allowed to run the course of its 
natural life like other more fortunate tropical insects. A 
few more years must pass before the artificial carmine 

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PAINTS, DYES, AND VARNISHES 

will completely supplant the cochineal product; but 
this substitution seems now absolutely assured. 

Such substitution is taking place, or has taken place, 
in the case of the other animal pigments, which need be 
mentioned here only for their historical interest. 

Lac-dye, once a favorite pigment material, is ob- 
tained from an insect not unlike the cochineal. The 
same is true of alkermes from which the famous Vene- 
tian scarlet was made. It comes from an insect found in 
Persia, Morocco, and Algeria. Purree, or Indian yellow, 
is manufactured in Bengal from the urine of cows fed 
on the leaves of the mango tree. Sepia, a favorite pig- 
ment of water-color artists, is made from the gland of a 
marine cephalopod, known as the " ink-fish"; while 
"mummy," an inferior yellow pigment at one time 
fancied by some artists, is made by the action of such 
solvents as chloroform or benzine on Egyptian 
mummies. 

The vegetable coloring- matters, like the animal, are 
of rapidly declining importance, as practically every one 
of them can now be made cheaper artificially than they 
can be obtained from natural sources. This means that 
certain great industries have been created at the expense 
of other older ones. Painters and dyers now look to 
city workshops for their supply of pigments that formerly 
came from the fields. 

Perhaps the most conspicuous example of the revolu- 
tionary effect of the introduction of coal-tar colors 
produced synthetically, is that of the complete elimina- 
tion of madder-root as a source of color-material. Mad- 
der, known botanically as Rubia tinctoruni, was cul- 

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SCIENCE IN THE INDUSTRIAL WORLD 

tivated extensively until recently, in many countries, for 
its roots, from which some of the most important lake 
pigments were made. The principal coloring-matter 
of madder was alizarine, from which a permanent red, 
and several other colors, invaluable for dyeing fabrics 
and making pigments for painting, were obtained. But 
alizarine is now made from coal-tar at a cost so much 
less than it is possible to produce the natural color- 
material, that the madder-growers have been obliged 
to plant their fields with grain and forego their time- 
honored vocation. 

The struggle of the madder-growers against the en- 
croachment of the new, laboratory-made product that 
was destined to engulf their industry, is a tragic page in 
the history of scientific advancement and commercial 
progress. English scientists had been foremost in pro- 
ducing colors from coal-tar; and as a result the estab- 
lishment of great manufacturing plants for making 
them were in progress. The increase of the madder 
industry of such establishments became apparent ; and 
so great was the influence of the madder-growers, that 
laws were enacted for protecting the older industry and 
curtailing the new. For the moment these laws proved 
effective; but only for the moment. Laws made for 
the benefit of the few and against the interests of the 
many cannot be long effective. The English artificial- 
color manufacturers, who were then leading the world, 
were ruined, but the manufacture of artificial colors 
crossed the Channel to France and Germany, and the 
madder-growers soon found themselves unable to com- 
pete with the foreign artificial colors which now flooded 

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PAINTS, DYES, AND VARNISHES 

the market. Before the restrictive legislation against 
home manufacture could be repealed, the French and 
German color-makers had gained a lead which the Eng- 
lish manufacturers have never been able to overcome. 

This legislation against alizarine manufacture was a 
repetition of somewhat similar legislation in several 
countries, a few centuries earlier, to prevent the importa- 
tion of indigo, long known to the East, but just then 
becoming known in Europe. Its brilliant color took 
the fancy of the wearers of colored silks as a satisfactory 
change from the prevailing reds and yellows which were 
the popular dyes of the time. The cultivation of the 
woad plant, and its manufacture into a yellow dye, 
constituted an enormous industry in many European 
countries, particularly Germany and England. The 
introduction of the strikingly beautiful dye, indigo, 
menaced every branch of this industry, and such pres- 
sure was brought to bear upon the legislators that strin- 
gent laws were passed forbidding the use of indigo for 
dyeing purposes. In the "free" city of Nuremberg, the 
crime of dyeing a fabric with indigo was, until the be- 
ginning of the eighteenth century, punishable with death. 

This famous dye is obtained from a plant that 
flourishes in the tropical regions of both hemispheres, 
the species Indigofera tinctoria being native to India, 
while Indigofera anil is the species of Central America 
and the West Indies. The dye-stuff is obtained from 
the plants by causing them to decompose in water. 
The pigmentary matter settles as a blue deposit, which 
is collected and carefully dried. 

Just at the present time the same element that 
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SCIENCE IN THE INDUSTRIAL WORLD 

stopped the raising of madder is stopping the impor- 
tation of indigo into Europe and every other civilized 
land, more effectually than legislation could ever do. 
Germany has perfected methods of manufacturing 
from coal-tar an indigo that swiftly and surely is re- 
placing the natural product. 

In point of age indigo is one of the oldest known 
colors. The Egyptians used it sometimes to color the 
wrappings of their mummies, and the fact that these 
wrappings still show the blue color attests the perma- 
nency of the pigment. The younger Pliny in his Nat- 
ural History gives a very exact description of indigo, 
and some tests for detecting it. Among other things he 
mentions that when heated over a fire it "burns with a 
purple flame and gives off a smell of tea." 

Until the opening years of the present century, 
artificial indigo was not able to compete with the natural 
product, about five thousand tons of which were used 
annually. But German manufacturers were perfecting 
methods, and in 1908 about one-fourth of the indigo 
used was of artificial manufacture. This leaves little 
room for doubt that it will be only a matter of a few 
years before the indigo-growers of the world will be 
obliged to devote their fields and energies to growing 
some other crop, probably less profitable. 

Logwood, the wood of Hcematoxylon campechianum, 
from which red, blue, violet, and black colors can be 
obtained, is another important New- World contribu- 
tion which the Spaniards discovered in South America. 
For four centuries it was one of the most important of 
dyestuffs, but, like indigo, it is now being rapidly dis- 

[310] 



PAINTS, DYES, AND VARNISHES 

placed by the artificial colors. The other vegetable 
coloring-materials, such as chlorophyl, dragon's blood, 
fustic, Persian berries, Brazil wood, gamboge, tumeric, 
litmus, redwood, and saffron have now been relegated 
to a place of historic interest only, so far as the com- 
mercial pigment- and color-maker is concerned. 

THE COAL-TAR COLORS 

The story of the discovery that the black, oily refuse 
of coal used in the manufacture of gas could be converted 
into coloring-material of every known shade and hue 
forms one of the most picturesque romances of ap- 
plied science. 

Thousands of centuries before man came upon the 
earth, in that particular period of the world's develop- 
ment known as the Carboniferous Age, there flourished 
everywhere in the hot, moist air luxuriant, gaudily 
colored vegetation. The huge animals and reptiles 
that wandered among the flowering trees and plants 
trampled them under foot in the mire, and the natural 
destruction of time and the elements piled them in con- 
stantly deepening layers upon the ground, where all 
the beauty they once represented was lost in the dirt and 
grime of their decaying surroundings. Succeeding ages 
piled layers of stone over this stratum of decayed vege- 
tation, burying it and compressing it into the stonelike 
substance that we know as coal. 

Seemingly, Nature had destroyed her creation of life 
and color, and had hidden every trace of her handiwork. 
But Nature does not create and destroy indiscriminately. 

[311] 



SCIENCE IN THE INDUSTRIAL WORLD 

The heat represented in its latent form in the growing 
plants, and the light transformed into their brilliant colors, 
were locked within the lumps of coal ready to be pro- 
duced actively whenever man should have found the way 
to do so. It took him all but the last two centuries to 
discover the relatively obvious fact that the heat could 
be extracted from this coal ; and all but the last half of 
the last century to unravel the complicated process of 
restoring the colors buried, and apparently lost, so many 
centuries before. That he has done so in scores of in- 
stances is one of the greatest triumphs of modern 
chemistry. What other achievement of man savors so 
much of the miraculous as this creation of hundreds 
of attractive colors and tints from this repulsive black 
refuse of grimy coal-heaps ? 

The conquest had its beginning in 1826 when Un- 
verdorben discovered aniline among the products of the 
dry distillation of indigo; and when Runge eight years 
later proved the existence of the same substance in 
coal-tar. The first aniline color was not produced, 
however, until 1856, when the English chemist, Perkin, 
produced "Perkin's violet." But this discovery was 
somewhat in the nature of an " accident," scientifically 
speaking, and the color could not be produced as a com- 
mercial commodity. It required Kekule's promulgation 
of the theoretical constitution of benzine, in 1867, to 
give the chemists a basis for accurate synthetic work. 
Until this time the discoveries had been empiric in 
character; but now the scientific production of colors, 
of greater or less value commercially, followed very 
rapidly. The most revolutionary discovery came in 

[312] 



PAINTS, DYES, AND VARNISHES 

1868, when Graebe and Liebermann effected the syn- 
thesis of alizarine, which proved the death knell to the 
madder industry. Ten years later Baeyer produced 
indigo commercially — the beginning of the downfall of 
the natural product. Since then important practical 
discoveries have followed each other with bewildering 
rapidity. Something like four hundred coal-tar colors 
are now in use for the manufacture of lakes; and the end 
is not yet. 

The amount of coal-tar available in ordinary coal is 
relatively small, the proportion being about one to 
twenty. But in the aggregate this amount suffices to 
supply the demand. The coal-tar colors on the market 
are usually in the form of a powder or crystals, the shade 
of which may be quite different from the solution. All 
of them are very complex chemical compounds, many 
of which, although identical in the number and kind of 
atoms in their molecules, are very different in color. 
The explanation of this seems to be in the arrangement 
of the atoms rather than in their number in each mole 
cule, but the exact nature of this peculiarity has not been 
determined as yet. After all, it is no more wonderful 
or difficult to understand that two substances, each 
having six atoms of hydrogen and seven atoms of carbon 
in each molecule, should, let us say, be blue and red 
respectively, than, to take a familiar example, that the 
chemically identical substances, charcoal and diamond, 
should be, one colorless and the other jet-black. 

The color-maker's interest in these coal-tar colors 
lies in their application to making lake pigments. In 
this process there is a very distinct and definite chemical 

[3133 



SCIENCE IN THE INDUSTRIAL WORLD 

action, which the manufacturer can produce with un- 
failing certainty; and yet "the theory of the formation 
of lake pigments has not been clearly enunciated." In 
many lakes there is this distinct chemical action, but 
not chemical combination. The salts used cause pre- 
cipitation, but not in the definite proportions that would 
result from chemical combination. Variation in the 
relative amounts of the color and the salt causes varia- 
tion in shade and color; but as this variation is con- 
stant, it is a concern of the chemist rather than of the 
practical manufacturer to determine the exact chemi- 
cal action. 

Many colors are produced by the combined precipi- 
tation of several salts and colors; and since so many 
colors are now known, the possibilities of combined 
precipitation are practically without limit. 

DYES 

While the various artificial colors, such as those 
made from coal-tar and those synthesized from other 
substances, are gradually revolutionizing the use of 
pigments in all fields where colors are used, a similar 
revolution has already been effected in the field of dye- 
ing fabrics. Natural coloring-matters, such as cudbear 
and logwood, which were formerly among the main- 
stays of the dyers, are now seldom used. For the 
artificial colors not only give a wider range of colors and 
shades, but are cheaper, and very much easier to use. 
It was as dyes, rather than as pigments for painting, 
that they were first introduced ; and while their applica- 

[314] 



PAINTS, DYES, AND VARNISHES 

tion as dyes differs from their use as paints and stains, 
their composition is identical. 

Without regard to the natural scientific grouping of 
artificial colors, the dyer divides them into six or more 
groups based upon their practical application. A recent 
grouping by Farrell is as follows: — 

i. Direct or substantive cotton dyestuffs 

2. Acid dyestuffs 

3. Basic or tannic-acid dyestuffs 

4. Mordant dyestuffs 

5. Vat dyestuffs 

6. Developed dyes 

The first of these, direct or substantive cotton dye- 
stuffs, are probably the most important to the dyer, as 
most of the colors are azo compounds, and dye vege- 
table fibers direct from an aqueous bath, with the ad- 
dition of some such salt as sodium chloride. Some of 
them are also adapted to dyeing such animal fibers 
as wool and silk, and the shades are usually very 
fast. 

The second of these, the acid dyestuffs, are the so- 
dium salts of sulphonic acids and the nitro-colors. 
These are particularly useful in dyeing animal fibers. 

The third, or basic dyestuffs, are substantive to wool 
and silk fibers, but may also be used to dye vegetable 
fibers. They are not very fast colors, however, and are 
not used very generally. 

The fourth, mordant dyes, are little used on account 
of the difficulty of applying them. The one color for 
which they are used extensively is Turkey-red on cotton 
textures, the color being produced from alizarine and 
an alumina lime and fatty-acid mordant. 

[315] 



SCIENCE IN THE INDUSTRIAL WORLD 

Vat dyes, or the fifth group, are difficult to apply, 
but they include the important dyestuff, indigo. 

The sixth group, or developed dyes, are produced in 
the fibers from the substances that are not dyestuffs. 
In this group come the important aniline black, and the 
colors produced by the combination of naphthols with 
the diazotized amido compounds. 

The number of these artificial dyes runs into the 
hundreds, and there are endless methods of applying 
them. As the composition of many of the colors and 
the methods of applying them are trade secrets, it is 
impossible to consider them individually, or to treat 
the subject in anything but the most general way. 

VARNISHES 

By all means the most important varnish — indeed, 
the only one known to most persons by that name — is 
the commonplace substance used as finishing for furni- 
ture, vehicles, interiors of houses, and a hundred other 
every-day things. To be sure there are several other 
rather common varnishes, such as damar varnish, 
which is made of a resin dissolved in an essential oil, 
and spirit varnish, of which shellac varnish is the most 
familiar example. But the importance of these is 
insignificant as compared with that of what is familiarly 
known as "varnish," without any distinguishing ad- 
jective, and which is a solution of resin in linseed oil, 
thinned to a certain consistency with turpentine or 
benzine. 

The process of making varnish constitutes a great 

[316] 



PAINTS, DYES, AND VARNISHES 

industry in itself, and even varnish of very high quality 
is made in large quantities in such factories. The 
apparatus for manufacturing is very simple, consisting 
essentially of a large copper kettle mounted on wheels 
for convenience in handling, and a chimney with a kind 
of hooded fireplace at its base. The fireplace serves for 
heating the contents of the kettle, while the chimney 
carries off the dangerous fumes and smoke. The copper 
kettle has a closely fitting cover, with an opening through 
which a stirring-rod may be inserted — an arrangement 
that has been in vogue for at least a thousand years. 

The first step in the manufacture of varnish is the 
melting of the resin. Lumps of this substance are placed 
in the copper kettle and run under the hood over 
the fire. As the resin melts it gives off a pungent and 
highly inflammable vapor, which is conducted off 
through the chimney by means of the opening in the 
cover of the kettle to which a pipe is attached. As the 
heat in the kettle increases and the lumps disappear, the 
liquid resin tends to foam, this tendency being controlled 
ordinarily by vigorous use of the stirring-rod. If the 
heat is so intense, however, that boiling-over is immi- 
nent, the kettle is pulled quickly out of the fireplace and 
allowed to cool a little. It is to meet such an emergency 
that the varnish kettles are mounted on wheels. 

During the melting-process from ten to twenty-five 
per cent., by weight, of the resin is driven off in the 
form of vapor. The temperature of the liquid resin 
rises to at least 650 F. by the time the mass is com- 
pletely melted. But both these things vary greatly in 
different resins. And it is not a common practice among 

[317] 



SCIENCE IN THE INDUSTRIAL WORLD 

varnish-makers to determine the stage of melting by 
the use of thermometers (as is done in experiments 
on a small scale in the laboratories) but to depend 
upon the " feeling' ' by means of the stirring-rod in 
the hands of an experienced workman. 

When the resin is dissolved, the kettle is withdrawn 
from the fire and allowed to cool a little, and the foam 
to settle. Meanwhile the requisite amount of linseed 
oil is being prepared in another kettle. This prepara- 
tion consists in heating it to a temperature varying be- 
tween ioo° F. and 500 F. according to the quantity, 
quality of varnish to be made, and individual preference 
of the manufacturer. The oil is added to the melted 
resin, the mixture being stirred constantly during the 
process. To all appearances a perfect solution results; 
but this is only apparent. If the mass were allowed 
to cool at this stage there would be a separation of the 
resin from the oil, and a cloudy mixture would result. 
Therefore the whole mass must be placed over the fire 
again, and heated until a drop placed upon a piece of 
glass no longer shows a cloudy appearance on cooling. 
In practice the manufacturer no longer depends upon 
this test, but is guided by the reading of a thermometer, 
keeping the mixture at a certain temperature for a period 
of time that experience has taught him is right for mak- 
ing the particular quality of varnish in hand. 

The immediate effect of the cooking, besides the 
essential one of causing the two substances to form a 
solution, is to thicken the liquid — to make it so viscid 
that it will require some thinner liquid, such as turpen- 
tine, to make it ready for commercial purposes. Both 

[318] 



PAINTS, DYES, AND VARNISHES 

undercooking and overcooking are likely to be harm- 
ful to the finished product. Undercooked varnish, in 
which the resin and oil have not combined thoroughly, is 
likely to disintegrate quickly when applied to a surface 
exposed to air and light. Overcooked varnish is likely 
to be darker in color and requires more turpentine for 
thinning. As this evaporates when the varnish is ap- 
plied, it leaves a thinner permanent covering, and af- 
fords less protection. 

The final process of varnish manufacture is that of 
adding the requisite amount of turpentine to the oil- 
and-resin solution. This amount has been accurately 
determined beforehand, and when the liquid in the 
kettle has cooled sufficiently it is added slowly with 
constant stirring. If this is done in the neighborhood 
of a flame, conflagrations are likely to occur, as the heat 
from the contents of the kettle volatilizes a certain 
amount of the turpentine, which is very inflammable. 
Carelessness in this matter is a not unusual source of 
conflagrations in varnish-making establishments. 

Benzine serves the same purpose in thinning varnish 
as turpentine, and as its cost is only about one-fifth 
that of the turpentine, it is used in cheap varnishes. 
It is very much more volatile than turpentine, and this 
is a disadvantage where fine work is desired. For 
this evaporation is so rapid that the varnish a sets" 
almost immediately, before the ridges left by the brush 
have time to be obliterated by the spreading and equaliz- 
ing process as in the case of the slower-drying turpentine 
varnish. 

The quality of the finished product depends upon 

[319] 



SCIENCE IN THE INDUSTRIAL WORLD 

three things — the care in making, the quantity of the 
ingredients, and their quality. It is needless to say 
that the best varnish cannot be made except from 
carefully selected resins, carefully prepared and re- 
fined oil, and highly refined turpentine. Everything 
else being equal, the relative amounts of these sub- 
stances determine the kind, rather than the quality of 
the varnish. 

The best representative of the spirit varnishes, and 
the one used preeminently in commerce, is shellac 
varnish. It is simply shellac resin dissolved in alcohol 
— a process requiring no heat, and no manipulation, 
although stirring hastens the process. The proportion 
of alcohol to the resin varies within wide limits, but in 
this country the usual proportion is about one part resin 
to one and a half parts alcohol. In this mixture there 
is not a complete solution of all parts of the shellac resin, 
as a waxy substance seems to be held in suspension. 

When a thin layer of shellac varnish is spread over 
a surface the alcohol evaporates almost immediately, 
leaving a thin, impervious film of shellac resin and wax. 
On account of this quick-drying quality shellac varnish 
is most convenient for any purpose. The drying takes 
place so rapidly that several coats may be applied in a 
very short time; but curiously enough, if too many 
coats are applied at short intervals, a thick, rubbery film 
is formed that does not harden completely even after a 
long time. It is good practice, therefore, not to apply 
more than two or three coats without allowing some 
little interval for drying. 

Damar varnish, the type of varnish made by dissolving 
[320] 



PAINTS, DYES, AND VARNISHES 

a resin in an essential oil, is a solution of damar resin in 
turpentine. As in the case of shellac varnish, the resin 
is not completely dissolved, and the solution is accom- 
plished without the aid of heat. Such a varnish never 
becomes very hard, and is not very durable. The film 
left by damar varnish is not simply a thin layer, but a 
combination of the damar resin and the residue always 
left by turpentine on evaporation. In this respect it 
differs from the spirit varnishes, in which the alcoholic 
solvent evaporates completely, leaving the original 
resin as the covering film. 

These three kinds of varnishes just described may 
be taken as the predominating types of varnishes in 
general use. But the number of modifications and com- 
binations of these, their mixtures with paints and stains, 
and their use in secret formulas of proprietary mixtures, 
which are placed on the market under many scores of 
names, is endless. Thus the "japans," which are 
numbered by dozens, are various combinations of var- 
nishes and driers; while lacquers, enamels, etc., are 
various combinations adapted to special purposes. To 
go into details about even the most important of these 
substances would require volumes; and even then the 
treatment would not be complete, since so many of 
them are patented trade-secrets, not available for 
publication. It suffices fully for our present purpose, 
however, to give a concise idea of the principal sub- 
stances used as bases for these combinations. 

vol. vm. — 21 



[32l] 



APPENDIX 

REFERENCE LIST AND NOTES 
CHAPTER I 

THE DEVELOPMENT OF THE TELEGRAPH 

In connection with this chapter the reader may advantageously 
consult any or all of the chapters in earlier volumes dealing with 
the development of electricity. The index will serve as a ready 
guide. There is also a reference list on the subject given in the 
Appendix to volume VI. under chapter VIII., "The Smallest 
Workers" (vol. VI., p. 324). Chapter VIII. itself, in vol. VI. 
(p. 148, seq.), will be particularly useful as dealing with the theories 
of electrical action. 

(p. 4). The full account of Stephen Gray's discoveries in con- 
nection with conduction and insulation of currents will be found 
in vol. II., p. 262 seq. 

(pp. 5-8). An anonymous communication suggesting the use 
of electricity for the purposes of telegraphy appeared, as stated 
in the text, in Scot's Magazine for February 17, 1753. 

(p. 11). The story of the discovery of the galvanic or voltaic 
battery is told in vol. III., p. 229 seq. 

(p. 14). Electro-magnetism gives new clues. The discoveries 
of Oersted and Faraday are recorded in vol. III., p. 236 seq. 

(pp. 21, 22). Dr. Jackson's alleged connection with Morse's 
discovery. The quotation is from The History and Progress of 
the Electric Telegraph, by Robert Sabine, C.E., New York, 1869, 
PP- 32-33- 

CHAPTER II 

THE SUBMARINE CABLE 

(p. 40). Enthusiasm over the successful laying of the cable. 
The quotation is from The Times, London, August 6, 1858. 

[3 2 3] 



SCIENCE IN THE INDUSTRIAL WORLD 



CHAPTER III 

WIRELESS TELEGRAPHY 

(pp, 62, 63). Marconi on the tuning of wireless messages. The 
quotation is from an article by Marconi in the Century Magazine 
for March, 1902. 

CHAPTER IV 

THE DEVELOPMENT OF THE TELEPHONE 

(p. 68). Dr. Robert Hooke's account of his telephone was 
communicated to the Royal Society in 1667. 

(PP- 73 ? 74)- Lord Kelvin's account of Elisha Gray's electric 
telegraph and Dr. Graham Bell's telephone is quoted from the 
Report of the British Association for the Advancement of Science 
for 1876. 

(p. 74 seq). Dr. Graham Bell's account of his invention of the 
telephone is taken from a lecture on "Researches in Electric 
Telephony" given by Dr. Bell before the Society of Telegraph 
Engineers, October 31, 1877. 

(p. 91). Wireless Telephony. The quotation is from an article 
entitled "The Latest Conquest of Space," by Beatrice Cassell, 
in Harper's Weekly for July 17, 1909. 

Somewhat more technical accounts of various apparatuses con- 
nected with telegraphy and telephony will be found in the Key 
and Index Volume in the section devoted to Mechanical Instru- 
ments and Appliances. 

CHAPTER V 

THE EDISON PHONOGRAPH 

(pp. 97, 98). Mr. Edison's description of the phonograph is 
quoted from The North American Review for May- June, 1878. 

For a somewhat more technical description of the phonograph 
and also for a description of the magnetic phonograph, known 
as the telegraphone, see the Key and Index Volume. 

[3 2 4] 



APPENDIX 

CHAPTER VI 

PRIMITIVE BOOKS 

A full account of the various types of ancient books with numer- 
ous fac-simile reproductions in tone and color may be found in 
Dr. Henry Smith Williams' History of the Art of Writing, New 
York and London, 190 2- 1903. 

CHAPTER VII 

THE PRINTING AND MAKING OF MODERN BOOKS 

Much of the material for this chapter is taken from A Short 
History of the Printing Press, by Mr. Robert Hoe. Mr. Hoe is 
undoubtedly one of the highest authorities on the subject and 
he has treated it fairly and without prejudice. The reader who 
desires further information may advantageously consult this book. 

(p. 131 seq.). A modern newspaper press. The quotation is 
from the New York Herald of May 10, 1891. 

(p. 135 seq.). The account of a perfected magazine press is from 
an article in the Century Magazine, by Mr. Theo. L. DeVinne. 

(pp. 142 seq., 149, 1 51-15 2, and 155 seq.). The descriptions of 
linotype and monotype machines here quoted are from the article 
on printing, by William R. Rossiter, in the Twelfth Census Report 
of the United States. 

CHAPTER VIII 

THE MANUFACTURE OF PAPER 

(p. 170). The force exerted by contracting paper. The quo- 
tation is from The Story of Paper-Making, by Frank O. Butler, 
Chicago, 1 90 1. 

(pp. 173-175). Paper from wood-pulp. Quoted from the 
article Pulp and Paper, by Charles W. Rantoul, Jr., in the Twelfth 
Census Report of the United States. 

(pp. 180, 181). Car wheels from paper. Quoted from The 
Story of Paper-Making, by Frank O. Butler, Chicago, 1901. 

[3 2 5l 



SCIENCE IN THE INDUSTRIAL WORLD 

CHAPTER X 

PHOTOGRAPHY IN ITS SCIENTIFIC ASPECTS 

The chapters on chemistry in vol. IV. may advantageously be 
read in connection with this chapter. 

(P- 2 35)- The Photography oj Color, by Chapman Jones, in 
Science Progress, 1908. 

(p. 241). From an address by Dr. C. E. Kenneth Mees before 
the London Society of Arts. 

(p. 242). From the address of Dr. Mees noted above. 

(p. 244). Scientific American Supplement, June 5, 1909. 

(p. 246). From an article by Friedrich Lummers in the Zeit- 
schrijt jiir Augeswandte Chemie, 1909. 

(p.246). From an article in La Nature, 1906. 

(p. 248). This, together with several shorter quotations in regard 
to color photography, is from Mr. Jones' account of the subject in 
Science Progress, 1908. 

CHAPTER XI 

PAINTS, DYES, AND VARNISHES 

A review of chapters on chemistry in vol. IV. will be of obvious 
service in connection with the subject-matter of the present chapter. 

(pp. 297-299). The quotation is from Painters' Colours, Oils, 
and Varnishes, by Geo. H. Hurst, London, 1906, a work which 
has been drawn upon for much valuable matter elsewhere in this 
chapter. 



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